Hello from Cuba

[Nowhere-Man]

My diagnostic of the volume pot has turned out to be correct. In fact, I'm quite pleased about that as lately everything felt a real struggle.
Today I did two things: First test the scale lamp bulbs with the 5 volts direct. One was seized in its holder so I had to remove the waveband scale (not the stringing). I cleaned that up a bit. The pot I removed carefully and used a good dose of servisol, while operating the switch. On repeating the former test with 9 volts + on the power lead and negative on the - pot lug, the set came on strong. My theory was the pot was somehow dragging down the voltage through tracking within (maybe yes, maybe no) but I was sure something was up.
I did as Miguel advised and checked for broken transistor legs - no breaks in the upper legs. I have to test the windings and then use the scope.
For now I am just working on the basics. It is working much stronger now.

[Refugee]

So it just needed a shot of switch cleaner and now we have got contact.
Try the scope on the top contact of the volume control and see if there is anything there.

[Nowhere-Man]

I don't have a scope yet. My tools are pretty good but my diagnostic equipment is basic at best. Feel free to recommend something economic.
The Servisol was recommended here by the members so I got some. Very good stuff.
One gripe I have is I feel I don't have a "normal" schematic but it's all sections. With the simpler valve radios you get the whole circuit on one page with notes and listings on the other pages. Still this is 1969 technology not 1953.
Still, as I struggle ahead it will be good experience for me.
I forgot to say connected to the volume and switch is a tone conrol spindle. This is incredibly dirty. Needs attention for sure.

[Nowhere-Man]

Gave the potentiometer more treatment today and now the on and off (plus volume) is working. Before it was totally dead. So, when I treat my Saalburg piano keys, I hope for equal improvement.
I examined Top-Hat transistors for breaks and seem OK. Made a gradual start to testing voltages on the board although work in freezing temps isn't all that pleasant. I notice my meter creates powerful audio responses on some solder points and I feel the audio section is fine. As others deduced, the RF stage seems to be the issue.
Was it a trick of sound or did I hear a quick blast of a station on rotating the band barrel? Not sure. I cleaned the contact points some more.
Attempts to tune MW using another radio created no response. The Astrad wasn't reacting.
I am almost ready to attempt RF testing but will just check my connections and voltages some more. What surprised me most is how the simple use of servisol on a pot can restore power to a dead set. Will definitely use it on the Saalburg.

[Nowhere-Man]

I made some pics for you all to see, starting with pic one here.

[Nowhere-Man]

And here we have the second pic of the радиоприемника ВЭФ 12 or Astrad Auriga as it was called in Europe.

[Nowhere-Man]

And now the 3rd pic taken today with my digital camera.

[Miguel Lopez]

That set looks in very good condition. Are those transistors mounted on sockets? If that is the case, did you removed them from the sockets to check the legs? Did you test the transistors with the meter to check that they are OK? Sorry, just elementary questions.

Really nice set. I'm now the happy owner of a couple of VEF-204 that a neighbourg gave me. He was going to dump them, and them he thougth on me. The sets look well by the outside, but I have not given them a look in the inside. I want to finish other projects now, before tune my self on radios for a while again.

[Nowhere-Man]

That set looks in very good condition.  Are those transistors mounted on sockets? If that is the case, did you removed them from the sockets to check the legs? Did you test the transistors with the meter to check that they are OK? Sorry, just elementary questions.

Really nice set. I'm now the happy owner of a couple of VEF-204 that a neighbourg gave me. He was going to dump them, and them he thougth on me. The sets look well by the outside, but I have not given them a look in the inside. I want to finish other projects now, before tune my self on radios for a while again.

I am currently doing some work on the USSR transistors. Since all of my experience to date has been with valves, I feel I need to do a crash course in Soviet transistors. Last night I found the P type and MP classification and read up on them a bit.

http://www.wylie.org.uk/technology/semic...oviets.htm

Another development is I now have a very good schematic for this radio.

I started by testing the emitter/collector voltages. This was strange because I was getting around 5 or so volts. Whereas with OC transistors on another radio I was getting around 7. Also strange is my scale lamps take 5 volts but are not lighting, even though I removed the bulbs and tested they work fine.

I don't know if there is any logic to testing emitter/collector voltage but I was curious and not sure if it tells me much.

I did check the legs and yes they are mounted in sockets. I didn't test for breaks in the sockets so I will do this as you suggest. I did notice the radio bursts into high pitched whistles if I disturb the transistors or tap them. They also go wild if I put the meter probe on.

I don't have a scope but I do know the RF stage is at fault and that (possibly) some circuit voltage may be cut off. Maybe people would suggest a good scope for me or even alternatives?

Why is there string bits emerging from the turret inside? I assume it is just string as no wire seems to be visible after scraping the end.

Not sure if I should start a thread on this radio apart although progress is likely to be slow as I learn more about transistorised circuits.

[Nowhere-Man]

I found this logo on a website:

"We workers of the VEF Radio factory of the Order of Lenin undertook the responsibility to undertake production of the highest quality. Should you notice any defects we ask you to inform the Repair Manager."
 
The question is, is it now a bit late to do just that?