Alba 472 volume control not working - UK Vintage Radio Repair and Restoration Discussion Forum

Daventry 5XX · 8th Mar 2012, 11:12 pm

Hi all

I've just bought a nice little Alba 472,it has a couple of problems that my limited knowledge cant resolve:

Firstly, the volume control does not respond it seems to be stuck at about mid-level.I've taken the pot off and metered it and it seems to be OK.
It goes from 0 ohms at one end to just over 1meg at the other,which is fine as far as I can tell (Its a 1 meg.pot)

The other problem is lack of reception ,LW is OK,but MW I can only get a couple of very faint stations and SW nothing at all.

I've given the wavechange switch a good spray with contact cleaner.

I have a good external aerial so I dont think that is the problem,I have also recapped it so I dont think any of the caps are faulty

Any suggestions on either problem gratefully received.

Alan

Steve_P · 8th Mar 2012, 11:30 pm

This is the same as the Aerodyne 302. You can get the sheet here:

http://www.service-data.com/product.php/136/416

If the volume control is OK, then the next thing to ask is 'Is it wired right'. It's R7 the circuit listed above. Middle (wiper) goes to the Top Cap of V3. (EBC33). The upper outer goes to C20, the remaining pin goes to Earth,

The other problem probably involves the capacitors and coils of the antenna side of V1. Look at C1, C2, C3 and C7. Have any of the coils been twiddled?

Cheers,

Steve P.

Daventry 5XX · 8th Mar 2012, 11:39 pm

Thanks Steve

I've got the Trader sheet,you are right it does cover the Aerodyne 302 as well.

I'll take a look at the wiring and the antenna side of V1 tomorrow.

Alan

8th Mar 2012, 11:12 pm	#1
Daventry 5XX Pentode Join Date: Dec 2011 Location: Daventry, Northamptonshire, UK. Posts: 163	Alba 472 volume control not working Hi all I've just bought a nice little Alba 472,it has a couple of problems that my limited knowledge cant resolve: Firstly, the volume control does not respond it seems to be stuck at about mid-level.I've taken the pot off and metered it and it seems to be OK. It goes from 0 ohms at one end to just over 1meg at the other,which is fine as far as I can tell (Its a 1 meg.pot) The other problem is lack of reception ,LW is OK,but MW I can only get a couple of very faint stations and SW nothing at all. I've given the wavechange switch a good spray with contact cleaner. I have a good external aerial so I dont think that is the problem,I have also recapped it so I dont think any of the caps are faulty Any suggestions on either problem gratefully received. Alan

8th Mar 2012, 11:30 pm	#2
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: Alba 472 volume control not working This is the same as the Aerodyne 302. You can get the sheet here: http://www.service-data.com/product.php/136/416 If the volume control is OK, then the next thing to ask is 'Is it wired right'. It's R7 the circuit listed above. Middle (wiper) goes to the Top Cap of V3. (EBC33). The upper outer goes to C20, the remaining pin goes to Earth, The other problem probably involves the capacitors and coils of the antenna side of V1. Look at C1, C2, C3 and C7. Have any of the coils been twiddled? Cheers, Steve P. __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

8th Mar 2012, 11:39 pm	#3
Daventry 5XX Pentode Join Date: Dec 2011 Location: Daventry, Northamptonshire, UK. Posts: 163	Re: Alba 472 volume control not working Thanks Steve I've got the Trader sheet,you are right it does cover the Aerodyne 302 as well. I'll take a look at the wiring and the antenna side of V1 tomorrow. Alan