Old Radio Q&A page

Welcome to my Old Radio Enquiries page. Last updated 3rd October, 2004..

Good-day to those who have patiently waited for my responses to their questions concerning radio valve information. Sorry for the long time before responding to some of you.
Please note: where folks e-mail addresses are quoted in this section they have all been modified by me by adding an extra word into that address; this is done to avoid the sad fact of spam-collecting activities that have become prevalent on the Internet in these times. The real address can be found by excluding this word. The word might just happen to be "antibot in various places / forms".

Well here goes with some questions, and where they are known, some answers:-
From: Mark Honts (mark.honts.antibot@mmwholesale.com) To: "'tgale@xs4all.nl'" (tgale@xs4all.nl) Subject: Radio Bar Dear Trevor, My name is Mark Honts and I am looking for information on an antique piece that I have. It is a Radio Bar. It had a Philco radio in the bottom of the cabinet and the top of the cabinet opens up into a bar complete with glassware etc. It is probably a 1930-1940 piece but I don't know for sure. I am trying to find out the value of the piece (without the radio), the approximate cost of restoring the piece (replacing the radio and speaker) and the value of the restored piece. I would appreciate any information you can provide. Please reply to this address or my personal email: frodo999.antibot@msn.com . Thank you for your time. Well, Mark, I certainly do not have any information to hand at the moment, so does anyone else out there have ideas about either the furniture or the radio that should go with it? Perhaps, Mark, it would help if you could tell us the measurements of the place where the radio went. Anyone's welcome to get in touch with me concerning this and I'll pass it on as usual, creditted of course, or contact Mark but please tell me as well.

Next I have a question from Peter Brack (Peter.Antibot.Brack@tgh.nhs.uk) To: "'tgale@xs4all.nl'" (tgale@xs4all.nl) Subject: Replacement Valve. Hi Trevor. Wonder if you can help, I have recently obtained an old radio gram which is not working, I have checked it out and I think No1 valve out of five is the problem.Valve ID{ X65} 8 pin masda octal base with a connection on the top and a lead to the tuning cap,I think it's a Triode-Hexode Frequency Changer.Can you tell me where I can obtain another if poss., Peter Brack Medical Equipment Service Manager. EX 6526. Well Peter, the X65 is indeed a triode-hexode mixer, and I can only suggest looking at the Buy/Sell section or the FAQ to find where to get a replacement. However I can tell you its' connections and characteristics as follows:-

[valve no.] [category] [base] [heaterv] [pinout] [Vanode] [V(g1)bias] [secondary info].
X65     TRI.HEXODE  AO8     6V 1:NC 2:h 3:a' 4:g2 5:g1 6:a 7:h 8:k T:g1'   250V  -3V    Vg2 = 100V.   cond = 1.2mA/V.

Next one concerning a rather elusive tuning indicator ('magic eye') From: "S.L.Kakkar" (slkakkar.antibot@universalcablesltd.com) To: (tgale@xs4all.nl) Subject: My dear Mr. F.C. Trevor Gale, I shall be grateful to you if you can send the Data & Base connection of the +following old radio valve EM-5. Best regards, P.Rajan
Well I have seached through my books to hand, and I find EM1, EM2 and EM4 but no mention anywhere of EM5. However looking at telia.com I found these excellent people indeed had some information on the valve: the display is of the 'segment' type, viewed from the top of the valve, and it has an AO8 base. Pins 2 and 3 are the heater which is rated at 6.3V, 0.3A. The common cathode, connected to earth/0V, is pin 4. It has, like many of such valves, an internal triode amplifier The g1 of the triode (input to the indicator) is on pin 6 and should vary from -4V to -20V for the complete display range. The triode has two anodes internally connected to the display beam plates; these are on pins 5 and 8 and should each be connected to +250V via their own resistors: pin 5 via 1 megohm and pin 8 via 2 megohm. Finally the target anode on pin 7 goes directly to +250V and draws some 0.45mA.

From: "volker jeschkeit@dnet.it" (volkerjeschkeit.antibot@dnet.it) To: tgale@xs4all.nl Subject: tube data 3C21 Dear Sir,I4m looking for data sheets,application and development story of the amperex 3C21 triode,all I found out,that it must be similar to amperex ZB120 tube.Thanks Volker from Italy
This sounds like a tranmitting triode although I may be wrong, but I have no data on it at all. Even a 'google' search revealed nothing at all, so if anyone can help us then please get in touch.

Next one from Eugenio Malaspina (eugeniomalaspina2002.antibot@yahoo.com.ar) Subject: Vintage tube radios To: tgale@xs4all.nl I've an antique radio Geloso Ducati Mod. RR 4080-RF 4085 4 bands, 1 m.wave and 3 short wave. It works with a pair or 6V6-GT (output), two 6SQ7, one 6SK7, one 6E5, a 6SA7, and a 5Y3 (although I use a 5U4). It has an +input jack and a phono-switch for record player.The radio has a good sound, but +the record-player doesn't sound that good. The volume of the sound of the +records is not so high and powerful as the volume of the radio; so that, you +get a very poor suound. The higher settings of the volume control give you an +"acceptable" sound. Though I got a new crystal pick-up, and changed the tubes +and a few capacitors, it didn't seem to do any good. Do you know which is the +problem? Thanks, Eugenio.
Eugenio, the first thing I would look at is the input jack and the switch, making sure that it isn't leaving some sort of extra load across the record-player input. Seeing as you've changed out the tubes and some capacitors, I would next look at cathode resistors (maybe gone high, leading to extra negative bias and so to less gain) and the cathode voltages accordingly. The same goes for anode load resistors. The other thing which should be checked is the fine wire from the pick-up to the place where it is connected at the other end: it could have leakage or more likely a partial open-circuit, losing signal. If you have another amplifier, or a set that can be used as one, try connecting the record-player output to this and listen to what the output sounds like - this way you know where the fault could lie.

Glenn Sprigg (gsprigg.antibot@cobweb.com.au) brings up the idea of making the valve data Web page also available as a 'zipped' document for easy and complete downloading: this is a possibility which I am considering, and I shall look at the idea again when I get time to look at how my pages are put together anyways. Thanks, Glenn, also for the correction of the typo '573GT / 5Y3GT' - I will update the page later on, I expect, so if anyone has more observations or suggestions don not hesitate to e-mail me with them.

A number of people have sent me e-mails asking for quotes, prices or sources for some radio valves: I would like all to know that the radio valve page which I (attempt to) maintain is really only for the technical information concerning old radio valves/tubes: I have no intention whatsoever of entering into the selling/buying/dealing in valves or valved apparatus. If you are seeking a particular valve/tube, and find it difficult to locate, then I will happily suggest where (maybe) it might be possible to find, but please don't send me 'orders' for a list of valves - this is not a shop!!! (Apologies to recipients who read this unneccesarily).

I thought I would deal with some sets of enquiries together in one e-mail and posting so as to disseminate as much useful data to those interested in one go. So here goes with anotehr set:-

1) Ralph Down (rjdown.antibot@fan.net.au) asks for information about a Philips tube type TB4/1250. From what I can look up this tube corresponds to the nomenclature used to 1984 by Philips: in this case, T = r.f. power triode, B = greater than 1W service, 4 = max.Va of 4000V, and the final 1250 = Po of 1250W. It is indicated for work to 100MHz, but I have an idea youi de-rate it above 50MHz. The pinout for this tube is:- (5-pin base)

1-f; 2-g; 3-g; 4-g; 5-f; TC=a.
Heater (directly-heated filament cathode) is 10V, 9.9A; Va = 4000; Vg = -350; Ia = 535mA; Adiss(max) = 450W; Po = 1430W; efficiency (in class C) is around 79%.

2) Dave Harrity (taoman.antibot@zoomnet.net) asks about a valve in an RCA Victrola V302 model, a turntable-radiogram. The glass identification GF6 seems to me possibly to be a 6F6, with no pin 6 present, equivalent to a KT63, connections for both are:

1-nc; 2-h; 3-a; 4-g2; 5-g1; 7-h; 8-k/g3
and it is an audio output pentode at 5W output with Va=285V and with Vg1 at -20V. It's an octal base (spigot between pin 1 & 8). The other valve near the transformer which glows brightly will be the rectifier valve of the power supply; it sounds like a directly- heated job but the number RE4 doesn't crop up anywhere I have seen. This, on the plastic body, may be a batch number or production number. I will look further on this one. I would have expected a 5U4 or similar rectifier here.

3) Sheldon Godinho (sheldon.antibot@smartnet.co.za) asks about using some 5687WA and 6072A (12AY7) valves. The 5687WA is a 9-pin B9A double-triode, pinout quoted as:

1-a'; 2-g'; 3-k'; 4-h; 5-h; 6-k"; 7-g"; 8-h(c.t.); 9-a" ...
BUT the envelope should be examined to check the real connections of pin 8 and pin 9 since the norm with series/parallel heaters on this base is that the heater center-tap is bonded to pin 9 (not 8) - I do not have one of these valves in my collection so I haven't been able to check this further. Vh is 6.3 or 12.6; Va = 250; Vg1 = -12.5; Ia = 16mA; mutual conductance is shown as 4.1 mA/V. The 6072 / 12AY7 is also a 9-pin double-triode, and the pin-out for this is as follows:
1-a'; 2-g'; 3-k'; 4-h; 5-h; 6-a"; 7-g"; 8-k"; 9-h(center tap),
used with parallel 6.3 or series 12.6-volt heaters. This valve's Va = 250; Vg1 = -4; Ia = 3mA; mutual conductance 1.75mA/V.

4) Mark R Trotman enquires of the Y808 tube resembling a 4CX250 but with heatsinks rather than blown-air cooling. It appears similar to a 4X150B, but that is from an old photo I have seen and I have no further data on that one. Anyone with some good data on this one, please send it in to me and/or Mark (mark.antibot@armscroft.demon.co.uk).

5) Wayne B'Rells enquires about substitutions for the 45 tube in push- pull applications. The 45 is a power triode, directly-heated, for audio output. It has a UX4 base, pinout:

1-f; 2-a; 3-g; 4-f.
Filament is 2.5V, 1.5A; Va = 250; Vg = -50; Ia = 36mA; Gm = 2.2mA/V. It gives some 1.6W output. Now if these valves are expensive to obtain where you are, it must be possible to select a 2A3 and de-rate the stage (the 2A3 is a 3.6W job) but where Wayne is, these are just as expensive. To keep the original base (and pinout) one could maybe opt for a change in heater voltage to 6.3V at 1.0A and use the 6A3, but it depends upon how easy it is to get the 6 volts. AN alternative, staying with the 2.5V filament supply, is to change the base to, say, UX6 and employ a 2A5 pentode connected as a triode, noting of course the reduced grid bias needed (-16V, not -50V), which could be done by reducing the cathode bias resistor (if present) to some 400 ohms. Unfortunately there is simply not a large selection of UX4 valves for this stage of a radio. Personally I would be tempted to give out the cash for the 45's for the sake of authenticity, but, as above, there are other ways of getting an 'acceptable' restoration. On this point, note that earlier-days service technicians and engineers would quite happily exchanged types in such a radio when the customer brought it in for service, so it wouldn't be too bad form to 'repair' it...

6) Jim Clark (GGW75A.antibot@prodigy.com) asks about replacing a VP-21 in a radio under repair. I suggest using an SP2V which has the same connections and the same heater supply requirements, both valves are around 1.1mA/V mutual conductance, but maybe 15 more volts on the screen for the SP2V (Vg2 = 75). An SP2 could also be used but the screen voltage is even higher (Vg2 = 125) and you would have to watch stability since the SP2 Gm is around 1.8mA/V.

7) Noel O'Keefe (nokeeffe.antibot@indigo.ie) has a Grundig radiogram with a missing ELL80 (a B9A double-pentode audio output valve). Now, I haven't the diagram of this Grundig, but if (as is usually the case) the ELL80 is driven by a double-triode such as ECC83, then a substitution can be made by removing the ECC83 and installing *two* ECL86's. The ECL86 is a triode-pentode audio amplifier & output valve. Both the ELL80 and the ECC83 valves use a B9A base, and both can use the common 6.3-volt parallel heater supply. It involves some re-wiring of the bases, typically one half of the ECC8x was used as the pre- amplifier, the second half as the phase splitter, so these functions would have to be taken up by the two triodes in the two ECL86's, but I have service material showing this was quite a common repair operation. In the above case, no component value changes at all should be necessary.

8) Chen Hanshan (carimbj.antibot@public.bta.net.cn) asks about the valve type 6550a. The only information on this valve that I have is that it is an 8-pin octal valve, with the following pinout:-

1-NC; 2-h; 3-a; 4-g2; 5-g1; 7-h; 8-k/g3. 
Pin 6 is not present on the base, the spigot as usual indicates the space between pins 1 & 8.

9) Francesco Mascitelli (mascit.antibot@rgn.it) seems to be asking after a Philips triode type TB4-10. Under the Philips nomenclature this is a transmitting triode, more than 1W output, at Va about 1000V; however I do not have any further information about this valve at all, so anyone with some good transmittable Philips memories is welcome to send me and/or Francesco such information - please!

10) Bob Martinengo (bobmartine.antibot@aol.com) wishes to know the pinout for the valve type 6AK5... This is a 7-pin HF pentode, the pinout is as follows:-

1-g1; 2-k; 3-h; 4-h; 5-a; 6-g2; 7-k/g3.

Right, well next, I have a question from Marianne (smileyantibot937@email.msn.com) asking about a 6V6G valve replacement. She writes:-
"Hello, I hope you can help me or give me some idea. I have a old floor model radio,that just has static. When i tested the tubes one came back as not working, it is a 6V6G. I noticed from your chart it is the only 6 tube that is not 6.3V what tube could be used as a replacement. Thank you, Marianne."
Well, Marianne, although it's listed as a 6V heater type, it's used just fine in 6.3V circuits; I have seen it listed as 6V and as 6.3V, and the 5 percent difference for this tube is well within it's tolerances. If after all, you need to think of a replacement, there's the possibility of using the 6L6, the 6P25, 7408, or a KT66. Eventually you might have to change a cathode resistor a bit, but they all should give you some sound at least.
Next, Alain Vergnes [email withheld] asks for any help to find a valve called "A258". I checked in my old AVO valve-tester book and that one's not even listed (there's an A242 and then an A303). It sounds like it might be a low-power transmitting valve for use at VHF or UHF, or maybe a receiver preamplifier valve; I'll keep on looking for that one and post you when I find it.
Further information shows the A258 was made by Visseaux and is the equivalent of the American 58 tube, a radio receiving valve. The 58 is a vari-mu R.F. pentode, UX6 base, Vh = 2.5V, Ih = 1.0A, and in other respects (except the lower heater voltage and the base) the same as the later 6U7G; Va = 250, Vg1 = -3V, Vg2 = 100V, conductance = 1.6mA/V, Ia = 8mA, Ig2 = 2.0mA.
The pinout is:
1:h 2:a 3:g2 4:g3 5:k 6:h TC = g1
Hope this late information helps.
And next, Hydrosolab.antibot@wanadoo.fr asks:-
"Hello, we try to find a pentode model 5CX1500A or equivalent. Do you sell this kind of model and if yes, what price ? Thanks you for quick answer. Xavier TORNE, HYDROSOLAB"
Again, sadly, I must re-iterate that my Valves/Tubes resource pages are not associated with any particular business or trade activity, and I also do not deal personally in purchase or sale of valves/tubes. Also, I wonder if it is the 3CX or the 5CX transmitting tube he is after... However if anyone else has an idea as to where to obtain such a tube, contact:-
Xavier TORNE,
15-17, rue Pasteur
Tel/fax: 05-59-27-19-93
e-mail: Hydrosolab.antibot@wanadoo.fr

On another note, Martin Chudley (mchud.antibot@ms.com) sends me the following interesting mail:-
"Hello Trevor,
As someone who played around with old TVs & radios in my teens, I have
a great affection for valves and old equipment and still have a few
biscuit tins full of various valves. I find your pages a fascinating and
nostalgic resource.

However, despite my "A level" physics and keen experimentation persued
about 18 years ago, I'd find it really useful to have a glossary or
appendix explaining phrases such as:
  "bad contact resistance, or a resistance or reactance of just a few
ohms can cause enough unwanted signal coupling to create instability".

I think you refer to any situation where an electrode of a valve in a circuit which should be effectively grounded at signal frequency: if such an electrode has (though dirty pins, etc) a resistance to ground, or if it is wired to ground by a long bit of wire (which could be quite an inductive reactance at the higher frequencies) then unwanted signal coupling could occur. Think of a grounded-grid triode amplifier stage: signal in at the cathode, output load at the anode. If the grid connection had a bad, or inductive, connection to ground, then some of the anode signal would be coupled back to the grid from the anode. Given certain combinations of inductance in the grid wire and capactiance from anode-to-grid, this feedback could cause wonderful oscillation at high frequencies. Finding the problem can be a nightmare - you bring your hand near the valve, holding a test probe or something, and the anode capacitance to your hand changes the whole set of parameters!
In short (excuse the pun) the attention here needs to be paid to clean connections in all circuits, and straight, short wiring in any signal-frequency circuits. Remember also: old decoupling capacitors may become dry and ineffective, giving rise to the same effects. In cathode circuits, the effect of extra unwanted resistance or dry decoupling caps is usually reduced stage gain.
He goes on:-
When I was young I subscribed to a monthly magazine called "Everyday
Electronics" which featured concepts, experiments and projects using
solid state components.  Do you know if there was an equivalent earlier
era publication referring to valve technology?  And whether anyone might
have made such material available on the internet?"
Well I remember both "Practical Wireless" (complete with Henry and his comments and cartoons) and Wireless World; both still exist today, the latter now known as 'Electronics World, including wireless world'. Practical Wireless used to often have projects that you could put together using a tobacco tin as the 'chassis', thinks like RIAA pre-amplifiers for record decks, and for antenna amplifiers for shortwave reception. Short Wave Magazine, of course, had quite a few radio amateur technical articles, but was naturally surpassed by the 'Bulletin' of the Radio Society of Great Britain (RSGB). The RSGB still runs with a healthy membership of amateur radio enthusiasts and experimenters, and it's journal is now names 'Radio Communication' ("RadCom") which you can subscribe to if you join the Society. Early bulletins, and other handbooks published by the RSGB in earlier days, make fascinating reading. It should be the case for early ARRL (American Radio Relay League) publications, too.
Well thanks again, Martin Chudley in London, E14.
Next, Roger Rehr (rrehr.antibot@epix.net) asks:-
Hi Trevor,

Do you know of any data on the UHF Power Tubes
YD 1302 or YD 1303 or YD 1304?

Thanks and 73 from
Roger Rehr  W3SZ ex-AA3QK ex-WA3JYM
mailto:rrehr.antibot@epix.net        FN20ah
Well, Roger, these valves are similar in that they are all forced-air-cooled trasmitting triodes for UHF work. They are of coaxial contruction: they are intended for the UHF TV band between 400 and 1000MHz. The YD 1302 has a Vf of 5V +/- 5% (tight heater-voltage spec), If of 2.1A, indirectly heated. It has operationally a Va of 1900V, Ia of 180mA, transconductance of 60mA/V, Vg1 of -6.6V in a video application, with 55W output into a load and a 19dB power gain. Cooling fins assist the forced airflow to cool the valve, and the maximum anode dissipation is 325W with an absolute maximum seal temperature of 150 degrees C. The 1303 and 1304 are steps upward in ratings from this valve. It is very specialized: if you wish to apply it, then you should contact Philips tube manufacturers of their representatives in your area.

Next, James Larson asks the following:
2 questions please

Sir- would you please suggest a couple of tube substitutions for me?
One is for a 50A1 in a Trans-Oceanic and the other is for a 1L6 in an
old Atwater Kent.

Thank You!

Jim Larson (james_l.antibot@efn.org)
Well, as for the first one, the 50A1 is an elusive number. What would help in seeking this valve is if you could indicate where in the circuit it appears (is it a frequency-changer stage by the looks of it, or is it coupled to an audio-output transformer by any chance?). It almost certainly has 50-volt, 0.15A heaters but tell me what base you think it is and it will be easier to locate this valve. The nearest I see is the 50A5, an audio output beam tetrode with a B7G base, or the 50B5 in an octal base.

The 1L6 is a frequency-changer heptode with the following pinout:-

1:f 2:a 3:g2 4:g1 5:g3/g5 6:g4 7:f
where the heater is directly-heated and is rated at 1.4V, 0.05A. Va should be around 90V in a mixer application, with Vg3/g5 at around 55V. There were quite a few of these series, like the 1L4 r.f. pentode, etc. The 1L6 is extremely similar to the DK91 with the same base (B7G) and dimensions.
Now an enquiry from KJ6C.ANTIBOT@SHASTA.COM (Carl SEGUIN) who asks:-
Hello. I recently found an RCA 9344 dated 1942. I have started a small
collection of tubes and I am interested in any information about this
particular tube. I have searched in some older RCA books that I have but
have found nothing. Any information you can provide would be greatly
appreciated. Thank you.
This one is a mystery to me, I have to admit. I also have a couple RCA books and I looked in my AVO checker book and a couple other equivalents books, but I don't see this or any similar (e.g. different prefix) valve crop up. As I mentioned in an earlier case, perhaps you could tell roughly what sort of application it was in (e.g. was it connected to an audio transformer, does it have a large envelope, what base does it appear to have?) so that I, or someone else with more knowledge, can dig up the information. Sorry, that's all I can do right now, I'll put it on my 'difficult' list.

Again, as I stated above in this page, I do not deal in valves, sale or buy. However because I get a very large number of requests (most of which I do not include in these updates) I thought I would pass on the following mail without further comment.
From: DB4203.antibot@aol.com
Date: Thu, 26 Nov 1998 21:27:26 EST
To: tgale@xs4all.nl
Subject: Antique Radios
My father is interested in selling his collection of hundreds of antique
radios and thousands of tubes.  If you are interested please contact him at:
Denzil R. Berry
*** (I have elected not to include the address given - Trevor Gale, author) ***
tel. (304) 762-2510

Next another difficult query concerning old European valves from Joco Henrique Melo (jhmelo.antibot@mail.telepac.pt) who writes:-
Is it possible to give me some information about the old european
E446, PP4101, E444, E443H, VG410.
Thank you, Joco Melo, Lisbon
The E445 and E446 were similar, both 4V-heater types on a B5 base. They are pentodes with Va=200, Vg2=100, and Vg1= -2V. The E445 had a conductance of 1 mA/V, the E446 had 2.3mA/V. E445 ran usually at Ia = 6mA, the E446 at an Ia of 3mA. They appear to be M.F. / I.F. amplifiers.
The E444 was a diode-tetrode, used as an amplifier and amplitude detector. It is shown on a UX7 base, with 4-volt filaments, Vg1 = -3, Va = 200, Ia = 1mA, Vg2 = 45, conductance 3mA/V.
The E443 is an output pentode (audio), still with 4-volt filament, a Va rating of 250V, Ia of 36mA, Vg2 = 240V, Vg1 = -15V, and with 2.8mA/V conductance. It is also on a B5 base. The pinouts for these are as follows:
1:a 2:g1 3:f 4:f 5:g2

1:k 2:h 3:h 4:g2 5:g1 7:a(d) TC=a(tet)

E445 and E446:
1:g2 2:g1 3:h 4:h 5:k

The following request I had was from gp.antibot.riojano@mx4.redestb.es "Grupo Parlamentario Partido Riojano" who kindly asked me in Spanish:-
Soy coleccionista de radios antiguas y para reparar uno de mis viejos aparatos,
necesito las siguientes valvulas: A-410-N(Philips), A-441(Philips), B-406
(Philips), C-9(Radiophotos), B-9 (Radiophotos) y D-100(Radiophotos)
Si  Uds. pueden vendermelas o ayudarme a encontrarlas les quedari muy
  Mi direccion postal es la siguiente: Leopoldo Virosta Garoz. c) Piqueras,85
26006-LOGROQO (Espaqa)  FAX. 941 22 88 73
Please, I am sorry for not responding in Spanish, although I understand your request. Unfortunately, I am not aware of many vendors or any other contacts who may be able to supply you with these valves; but you might be able to use equivalents based on the following information:
A410N: directly-heated triode amplifier with Vf = 4V, If = 0.06A, Va = 150V,
Ia = 3.5mA, Vg1 = -3V, base B4 with pinout:-
1:a 2:g 3:f 4:f

A441N: directly-heated tetrode, Vf = 4V, If = 0.08A, Va = 100V, Ia = 4mA,
with base B4 pinout:
1:a 2:g1 3:f 4:f TC = g2

B406: directly-heated triode, Vf = 4V, Ih = 0.1A, Va = 150V, Ia = 8mA,
Vg1 = -15V, base B4 pinout:-
1:a 2:g 3:f 4:f (it was also made in base 'USM4', 1:f, 2:a, 3:g, 4:f - measure
the heater pins with an ohm-meter to check!)

B9 is the direct equivalent of A410;

D100 is equivalent to the B443 (Philips) which is a directly-heated output
pentode, with a Vf of 4V, If = 0.15A, Va = 250V, Ia = 12mA, Vg2 = 150V,
Vg1 = -15V on a B5 base:-
1:a 2:g1 3:f/g3 4:f 5:g2
I hope this is of some help to you. Saludos y feliz navidad.
Lastly this session, I received the following from ROSENRO.ANTIBOT@mail.northgrum.com ("Rosenburg, Ron") with the following enquiry:-
Do you have any info on the Amperex 211-D tube and the Anodyne 866 tube? (I
thik they are for short wave) What are they used for and any tech data? Year
of manufacture?
Any help would be greatly appreciated.
Thanks, Ron.
Well, Ron, the 866 appears to be a U.S. rectifier tube, in a 4-pin base, with two version available - the 866/A and the 866B. They are both directly- heated half-wave (single diode) recifiers, the 866/A has a Vf of 2.5V and an If of 5.0A, Va = 3500V, Ia = 250mA, with the pinout:-
1:f 2:NC 3:NC 4:f TC = a
As regards the 211-D, it is indeed an Amperex transmitting tube, equivalent to the HF140 (also Amperex), a directly-heated triode with a Vf = 10V, If = 3.25A, Va = 1250V, Ia = 175mA, max full-rating frequency of 15MHz, air- cooled, amplification factor 12, 150W carrier output, maximum anode (plate) dissipation of 100W, but I do not have the connection pin-out. They are listed in my 1954 manual, so they were made on or before that date.
* * *

Oh, and just to show that there always exists the possibility of mis-understanding about subject matter, I received the following in response to my valve data page:---

"Dear Sir

Se woo Conval is one of the valve suppliers/manufacturers in korea and we are
professionally supply a broad range of manual and control valves to commercial
plants such as steel manufacturing plants, petro-chemical plants and automobile

We produce not only common valves  but also special type of valve.
nuflo is the special valve which has an actuator inside.
Due to equip an actuator, it has compact design and economic price.
nuflo also guarantee 3 times longer seat life time than other  conventional one.

If you have any question about our product, please contact with us."
Not exactly the same type of 'valve' that *we* are interest in, eh? !!!

Glenn Sprigg (gsprigg.antibot@cobweb.com.au) brings up the idea of making the valve data Web page also available as a 'zipped' document for easy and complete downloading: this is a possibility which I am considering, and I shall look at the idea again when I get time to look at how my pages are put together anyways. Thanks, Glenn, also for the correction of the typo '573GT / 5Y3GT' - I will update the page later on this week, I expect, so if anyone has more observations or suggestions don not hesitate to e-mail me with them.

A number of people have sent me e-mails asking for quotes, prices or sources for some radio valves: I would like all to know that the radio valve page which I (attempt to) maintain is really only for the technical information concerning old radio valves/tubes: I have no intention whatsoever of entering into the selling/buying/dealing in valves or valved apparatus. If you are seeking a particular valve/tube, and find it difficult to locate, then I will happily suggest where (maybe) it might be possible to find, but please don't send me 'orders' for a list of valves - this is not a shop!!! (Apologies to recipients who read this unneccesarily).

Now, another tip as to where to (possibly) obtain valves/tubes and other old bits and pieces - someone in Australia has apparently collected much material over the years and wrote:

"As I hate sending perfectly good gear to the rubbish tip, over the years
I have gathered some valves and old bits and pieces which I would like
to make available to those who can put it to good use ... hence there is
a section of our site listing this stuff."
The Web address he gave me for this was at http://www1.tpgi.com.au/users/hadrecs/VintageData00.html and might well be worth looking at.

Nils Hornfalk (nils.antibot.hornfalk@seind.mail.abb.com) recently bought a valve amplifier called a PAM-Samson. He says it has a 5Z3, a 6Y7G octal, and a 6J7 metal octal plus a 42 (or 6F6). He also asks for data on the ECLL800 valve as well. Well the 5Z3 is a full-wave rectifier tube, base UX4, with the following pinout:

5Z3:- 1:f  2:a"  3:a'  4:f  Vf=5volts, If=3.0amp, Va(rms)=450, Ia=670mA.
The 6Y7G data I don't have to hand at this moment, but it would also seem to be a rectifier and I wonder why there would be two rectifier tubes in such an amplifier....

The 6J7 is actually an R.F. pentode, octal base, indirectly-heated. With the exception of the metallization and encapsulation, the 6J7, 6J7G and 6J7GT are electrically and pinout-wise identical, and as follows:

6J7:- 1:s 2:h 3:a 4:g2 5:g3 7:h 8:k TC=g1  Vh=6.3V Ih=0.3A Va=250 Vg2=100
      Vg1= -3  Gm=1.25mA/V.

The 6F6 is an audio output pentode, equivalent to the KT63, and has an anode dissipation rating of 11 watts. Anode impedance is around 80Kohm, but with an optimum load of 7Kohm audio primary. The pinout is as follows:-

6F6:- 2:h 3:a 4:g2 5:g1 7:h 8:k/g3  Va=285 Ia=38mA Vg1= -20 Vg2=250

and is usually operated with a cathode bias resistor of some 390 - 470 ohms.

As for the ECLL800, this is a triode+double-output-pentode valve, usually used in circuits where the triode serves as a phase-splitter to drive the two associated pentodes in 'push-pull' - please also look at the replies quoted below this paragraph.. I can find no quoted equivalents for this valve, which is of European origin. From memory, I would treat it as an ECL82 with an extra pentode in the same envelope, but look at the base connections to the valve electrode connections to establish the pin-out, it must have a common cathode for all 3 valve functions, with the input signal being fed to g1 of the triode and g1 of the first pentode (using a common connection), the anode of the triode supplying output via a capacitor and bias resistor to g1 of the second pentode (in anti-phase), g2 of both pentodes being common, and g3 of both pentodes being bonded to cathode. With 2 more connections for heaters you have a complete 9-pin set when you include the two output-pentode anode connections to the push-pull output transformer. Please note that I will ascertain the actual connections during the next couple of weeks before you might use this information. If anyone else has information on this valve in advance of my searching, please e-mail me at mailto:tgale@xs4all.nl and I would appreciate the effort.

In fact, and very quickly indeed, I have had a response about some of these tubes and I include it here with grateful thanks to the sender. Here it is (Thank you, Douglas Dawson - dawsondc.antibot@postoffice.worldnet.att.net :-

 From: Douglas Dawson  Jun 4, 1998 11:30
 Here is some information on US tube types which you mentioned in your
 most recent missive.
 1. US type 6Y7G is a dual power triode intended for zero-bias, Class B
 service. It is equivalent, except for the octal base, to US type 79.
 Pinout, in your nomenclature, is:
 1:s 2:h 3:a" 4:g" 5:g' 6:a' 7:h 8:k
 In the amplifier mentioned, the 6Y7G is probably the final power
 amplifier, driven by the 6F6 in triode connection.
 2. Type 6SS7 is a remote-cutoff (variable mu) RF pentode, electrically
 equivalent to loctal type 7B7. The closest equivalent is probably type
 6SK7 (equiv: 7A7) which is also a remote-cutoff type and has the same
 base and pinout. Heater current for the 6SK7 is 0.3 amperes instead of
 0.15 for the 6SS7. Transconductance for the 6SK7 is slightly higher and
 anode resistance slightly lower.
 3. I, too, cannot find anything on a type 952. Most of the 95_ series
 are "acorn" style tubes which are not likely to be found in a consumer
 product as they were mostly used for the military or industrial
 4. Most of the US types mentioned are readily available by mail order in
 the US for around 5 USD. Here are two URL's for US businesses supplying

...and he quotes these URL's as follows:- http://www.tubesandmore.com/ and that at http://www.cinternet.net/~vactubes/ which might be worth looking at.

I have also had a response regarding the ECL800 valve, and I quote some of this with thanks to Scott Robinson under the subject: Tube 6KH8/ECLL800 Pinout?

-I wondered the same thing when first I encountered this tube.  It's like
-this(I have edited the pinout format - FCTG):-
-1:a 2:gt and g1 of Pentode-1 3:a'p 4:h 5:h 6:g1(Pentode-2) 7:k(common)
-8:a"p 9:g2(both pentodes)

-Whew!  Useful item, pity they are so expen$ive...
Thanks again, Scott.

Next, Anne Forbes (dragonette.antibot@geocities.com) tells me that she would like help regarding a Philips 'radioplayer' model 177. She would like to know how old this apparatus is and something about replacement valves if and when it breaks down. She has the instruction booklets but no date of manufacture, etc.
Well, Anne, you may already know that the Philips organisation is based right here in The Netherlands (Holland to many) in the city of Eindhoven, although they have many other plants over the world. I have the 'radio-vademecum' (a fairly complete listing of old Philips (and other) radio and record-player models of the type, and this shows me models such as the 707A, the 707U, the 709A, the 710A and so forth which are all radio-gramophones - but I have not found reference to the 177 model you quote. All the others I just mentioned were from the years 1940-41; however the model you have may well be an export model not catalogued in this reference.
In general, I would recommend that (a) you examine the valves to ascertain their type numbers, and then refer to my (or other's) valve data pages to find out replacement data if and when required, and (b) look at the cylindrical 'capacitors' (or, 'condensers' as they were then called) which probably have values on them such as '16uF' or '8 mmf' or '25micro-F' stamped on them - they often also have their production date written on them as well, which gives an idea as to the age of the set.
Again, I promise to look further to see if I can find an absolute reference to the model you seem to have - perhaps you could e-mail me with the details of any labels or information you can see on the rear of the set. This would help me in further identification of the model.

Next, I was asked about the transmitting tube used in many amateur radio sets commercially manufactured (such as the KW2000A from KW Electronics) which is the 6146 and it's variants...
Well, the 6146 has often been used, usually in pairs, in many of such sets, and is described in the R.S.G.B. (Radio Society of Great Britain) publication 'Radio Communication Handbook' and is also mentioned in the ARRL Handbook from the equivalent American society.
The 6146 has the following pinout:-

6146:-  1:k/bp 2:h 3:g2 4:k/bp 5:g1 6:k/bp 7:h 8:base-sleeve TC=anode.

The 6146B is the more ruggedized version of the valve; a pair of them is good for some 150 watts of R.F. output up to 30MHz with some room to spare, in C.W. mode; simple cooling arrangements should be sufficient.

I continue to receive requests for obtaining or purchasing components and in this respect Ken Crum (Cadd55Ken.antibot@aol.com) asks me how to obtain two PX25 valves for his Decca DECOLA which he is restoring. I am sorry to have to repeat this, but I am not in any way involved in the sourcing or selling of tubes/valves or any other components but I understand that in many places it is difficult to find out where/how to get spares for our hobby. I can only recommend some of the site(s) that I have noted in these pages, and by all means would anyone who can help please E-mail me or the person in question if they have an idea where such purchases may be made - but please do not ask me for components for sale.

randrend.antibot@euronet.nl enquired about the EL34 pentode valve. This is an audio output pentode, sometimes used in push-pull using a pair of them, and is equivalent to 6CA7 and KT77. The heaters are 6.3V, 1.5A. Used in single-ended class-A, the ratings are: Va=250V, Vg2=250V, Vg1= -12.2V, Ia=100mA, Ig2=15mA, Ra=15Kohms, gm=11mA/V; this with a cathode resistor recommended as 100 ohms, an anode load of 2Kohms and giving Pout of 11 watts.
Used in push-pull, the ratings are: Va=375V, Vg2=275V, Vg1=-33V, Ia=110mA, Ig2=23mA, anode-to-anode load = 3.5Kohms, giving a power output of 40 Watts. The pinout is as follows:

1:g3 2:h 3:a 4:g2 5:g1 6:NC 7:h 8:k

Gary Harris (gwharris.antibot@primenet.com) is restoring a Hammarlund HQ-129-X receiver, and looking for 6SS7 (r.f. / i.f. amplifier valves) and 6K8 (l.o/mixer valve). The 6K8 is categorised as follows:-

6K8G    TRI-HEXODE  OCTAL 6.3V      2:h 3:ah 4:g2/4 5:g1 6:at 7:h 8:k TC=g3
        Va=250V   Vg1=-3V  equivalent to WTT128.
The 6SS7 is something more of a mystery and I am wondering if this could possibly be substituted by something like a 6SG7 (vari-mu R.F. pentode) or a 6SH7 (straight R.F. pentode) - both these have the same pinout as the 6SS7 except that pins 3 and 5 are connected together as a common k/g3 connection. The pinout for the 6SS7 was as follows:-
1:s 2:h 3:g3 4:g1 5:k 6:g2 7:h 8:a
From the type number I would assume it has a 6 or 6.3-volt heater, like the 6K8 has.

CHAROBS.ANTIBOT@aol.com enquires about a tube type 952 in a Magnavox radio/turntable some 50 years old. I cannot find anywhere a reference to that number, but the function is more or less certain to be that of an amplifying triode. There are two apparently similar triodes with this type of base, the 955 and the 957 / 958. The 957 and 958 are directly-heated filament-cathode triodes with the following pinout:

957 / 958:- 1:f+ 2:a 3:g 4:f- 5:f(ct) - used as cathode connection.

The 955 is also such a triode, but with an indirectly-heated cathode, and with the following pinout:-
955:-       1:h  2:a 3:g 4:h  5:k

I would be tempted to examine the heater circuitry and select one of these as a possible substitute if necessary.

Jukka Rahikainen (jukka.antibot.rahikainen@icl.fi) is examing the Telefunken set he has on his hands containg an AL41 output pentode, an ABC1 double-diode-triode, and an AZ1 rectifier valve - and asks about the pin-outs for these valves. Well, Jukka, the 'A' prefix to these type numbers implies that they are 4-volt heater types as you mention. The AZ1 is a 4-volt version of the EZ1, for about 30mA rectified current. The pin-out would appear to be as follows (from my AVO test-meter book):-

AZ1: 1:NC 2:f- 3:f+ 4:NC 5:a' 6:NC 7:NC 8:a"
The ABC1 valve, from the same source, would appear to be as follows:-
ABC1: 1:NC 2:f- 3:f+ 4:k 5:a"diode 6:a'diode 7:NC 8:a(triode) TC=g1.
      Va=250V, Vg1= -7V, Ia=4mA, gm=2mA/V.
Unfortunately, the AL41 seems to evade my sight at the moment, but I would bet that it could be similar to the UL41 but with the 4-V heaters.

Jim Tiano (james.antibot.tiano@exgate.tek.com) has sent me a request concerning the characteristic curves for the 76 valve. The 76 was a general-purpose triode, with the pinout as follows:-

76:  1:h 2:a 3:g 4:k 5:h

and this tube has the following characteristics in an amplifier application:-
Vh=6.3V Ih=0.3A; and you can select from two sets of data I present here:

      Va           Ia             Vg1         Ra         Gm
(a)   100V         2.5mA          -5V         12Kohm     1.15mA/V
(b)   250V         5.0mA          -13.5V      9.5Kohm    1.45mA/V

The grid-anode capacitance is 2.2pF, grid-cathode is 3.4pF and the anode-to-cathode capacitance is 5.5pF (quoted from Brimar data).

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That's all for this time, thanks very much to those who have passed on comments on the valve radio page of mine, and here's to the restoration of our old-fangled devices with things inside where you *can* count the pins 8*) !

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E-Mail... You can E-mail the author of these pages (Trevor Gale) by using this link. on the Dutch Internet service provider XS4ALL.

Go Back Click on this link to go back to my main valves page.
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