PA2TG (Trevor Gale)'s Station News Page.

So here is the latest news from the PA2TG station activities, updated to this page on 26th December 2011 at 02:04 am local.
The very latest from my workshop: the finalized version (version 4) of my video processor has now been completed as far as the video side of things is concerned. It is far more stable and at the same time flexible (if you know what you're doing and choose to use one or more of the 'manual' controls rather than the in-built automatic ones). Here's an idea of the basic board layout:-

All that remains to do now is the audio side of things, including auto-A/V reduction when the microphone is used, audio vox, and tone equalization plus adaptive noise reduction. All of this latter enables the best to be got from the audio as well as the video when, for example, re-sending received ATV from another band, or replaying received ATV from another station that was recorded previously.
I've decided to build a reduced version of this processor, for use on the receive side, to make the most of live ATV received from other stations as well.
I am currently spending a little of my time as I recover from recent events upon the updating and adding-to of my various webpages and sites. In the process there may be the occasional "bug" left around (but not harmful ones) so my apologies in advance for things like things being mentioned but not showing up.

Firstly, an excellent illustration of the usage of the English language sent to me by an observant girl whilst in Scotland; read, inwardly digest and subsequently understand! Click on the image below for this - and a little more!!!!!!

A NEW A.T.V. introduction / test video is now available, and since there are so many different video decoding and playing software options available for one's computer nowadays, I have elected to make it available via the YouTube resource facility which is far more universal and more widely acceptable.
You can view it (it is approximately 4 minutes long) by clicking this link here.

There is now a new section in the PA2TG set of pages, one devoted to occasional device data and datasheets, and this can be accessed from the main PA2TG intro page - the one you came here from.

Now next, the original 10 GHz ATV (Amateur TeleVision) transmitter driver and P.A. have been finally installed, and the driver itself has been partially upgraded. The original driver prototype modelled by my good theatre/photo friend can be seen below on the left and the somewhat revised version of that in actual use can be seen aside below on the right (enlarge by moving over).

This has proved itself as a working basis for a further update for the design of a newer 3-cm ATV driver based upon the same principles and approach but with a more compartemplised interior structure providing better screening and less interaction between modules than is presently the case. Without going into fine detail, the fundamental operation of the 10 GHz ATV transmitter here is of a kind of 'split VCO plus PLL' that is effectively shared between the electronics unit on the antenna mast and the associated electronics at the 'shack' or indoors end. This is realised by the use of microwave R.F. circuitry and amplification at the antenna end which issues the transmitter signal the divided-down reference frequency which is sent down to the indoors unit. This, in its turn, detects this divided reference and counts it, comparing it to the desired operating frequency and generating an appropriate voltage to set this frequency such there is no difference, i.e. the transmit frequency is then equal to the desired frequency set in the indoors unit. Added to this is of course the modulation, both video and sound-subcarrier which is itself frequency-modulated, the result being a composite baseband ready to be frequency-modulated as appropriate for the 10 GHz transmission.
Added to these signals are a subset of other data lines to and from the mast-head electronics unit such that operation temperature, transmit power level, and reflection can be monitored from the shack (indoor) units metering.
In accompanient with this is the final P.A. controller and power distributor, an impression of which can be seen below:-

and which as can be seen shows the state of measurements including mast unit temperature and 10 GHz R.F. power output in addition to the usual voltage and current metering for the end stages themselves.
*** IT IS CURRENTLY THE CASE that there may be a fault issue with the end P.A. stage of this transmitter, as is shown on the in-built metering, and this will have to be investigated in the future as at this time I am personally not in a situation to climb the roof and/or antenna mast to perform such work as I would normally do.

Here is also a new view of the antennae on the main mast here at PA2TG, this can be seen below: note that there are sometimes several antennae for the one band/frequency, notably for TX and RX of A.T.V. and sometimes separately for normal SSB/FM purposes. Here is that stack - remember there are also two other stacks of antennae that are not located on the main mast (move over to enlarge):-

ANOTHER new feature which is now, currently, in the process of being realised is of a Web-based 'repeat' of my 10 GHz ATV monitoring receiver, this is not currently in the so-called 'public domain' but restricted to those with knowledge of the URL and so on because otherwise the bandwidth issues would potentially become prohibitive. However, an example of how this repeated ATV monitor image looks like is here below:-

and this image is normally shown much larger, at 640 x 420 in size.

There admittedly are still a number of bugs in this facility but they will be worked upon as time allows - remember please, the Web side of things here at PA2TG takes a second or even lower priority to other activities which occupy significant time here. I share the thoughts of the great Bob (R.A.) Pease of National Semiconductor, now unfortunately deceased, in that as a hardware man (not a computer man!) my favourite programming language is Solder!.

Also, here, a number of pictures of the recent radio/ATV activity that have been recorded can be seen: they will not be refreshed here like they are in the links called in the A.T.V. and maybe other sections of this site.

First the ATV status screens.......:- Then the 'amateur radio' shelf.:-

And the operating area................:- Here the main operator if there:-

The recent transmit ATV image..:- The radio/T.V. station monitor..:-

And the radio/ATV station used.:- The selected TV transmit frame:-

And the selected receive frame.:-

That's all for now - my good 73's and 88's as appropriate, de PA2TG.
You can E-mail the author of these pages (Trevor Gale) by using this link, or by sending mail to tgale@tgale.net on the Dutch Internet service provider XS4ALL.