Bush 82CL squealing

[Stylo N M]

It is possible to replace certain foil would hunts capacitors with ceramics, but you would have to look closely at the circuit, or circuit diagram, and understand what each capacitors function is to determine if a ceramic capacitor replacement would be exceptable (others may beable to advise)

Personally i would be inclined to replace like for like, and replace them with the modern equivalent, the yellow polypropylene foil wound capacitors, which will almost certainly be ideal for your radio.

Paul

[Graham G3ZVT]

Originally Posted by Radio Scotland

Could anybody tell me if it would be ok to replace the three hunts capacitors with ceramics ?

Cheers

Ceramics are absolutely fine.

[Radio Scotland]

Originally Posted by rambo1152

Ceramics are absolutely fine.

Much appreciated.


Cheers
Jay..

[Radio Scotland]

Recapped the radio and put it back together and noticed LW was a mile off frequency Turns out a small cap had broke off on the band selector. Soldered it back in place and got LW working again then the band selector decided to play up. Whilst i was trying to fix it the radio suddenly went dead


A quick tap on the oscillator transistor and it burst back into life (AF-117)

After using a ton of cleaner on the band selector it started working as it should. Put it all back together (again) and its still giving me grief on LW. works most of the time on LW with a hard press of the selector. The contacts look very worn. Sounds great after the recap, And sensitivity is great. Also installed a battery tray for 6 x AA Batteries.


p.s most of the original caps were miles out of spec

[Sideband]

You can try 'blasting' the AF117 if you have access to a power supply of about 25V (or maybe stringing two or three PP9's together might work). Take the AF117 out, connect emitter, base and collector leads together leaving the screen lead free. Apply the 25V between the shorted leads and the outer casing. Any tin whiskers inside the transistor should be burnt away by this process, refit the transistor and it should be working. This process doesn't stop the whiskers growing back but hopefully it will remain working for a long time.

[jonnybear]

Good to see all up and working. The best piece of kit for cleaning wafer switches I have found is one of these fibre pens, switch cleaner does not clean the tarnish off of 50 year old wafer contacts this will, a good investment for future repairs. https://www.ebay.co.uk/itm/Fibre-Fib...8AAOSwImRYFHXZ.
John

[Radio Scotland]

Originally Posted by Sideband

You can try 'blasting' the AF117 if you have access to a power supply of about 25V (or maybe stringing two or three PP9's together might work). Take the AF117 out, connect emitter, base and collector leads together leaving the screen lead free. Apply the 25V between the shorted leads and the outer casing. Any tin whiskers inside the transistor should be burnt away by this process, refit the transistor and it should be working. This process doesn't stop the whiskers growing back but hopefully it will remain working for a long time.

I already done that when i first got the radio and it brought it back to life. I have replacement transistors. But i'll keep it running on the originals till they finally pack in.

Cheers'


Jonnybear, The mystery component did indeed turn out to be the AGC Capacitor (8uf) Thanks for the advice regarding the fibre pen

[Radio Scotland]

Must say i'm very impressed with how sensitive this radio is. Iv'e just been comparing it against a modern radio and the bush wins hands down. The sound quality is good too even though it's not got it's original speaker. But the speaker is from the same time period. And the squealing seem's to have gone. So all good.

[Sideband]

I'd agree with you on the sensitivity. I was always surprised at how good it was particularly at night. Caroline also comes in quite well.

[Radio Scotland]

Originally Posted by Sideband

I'd agree with you on the sensitivity. I was always surprised at how good it was particularly at night. Caroline also comes in quite well.

Well i'm listening to spirit radio at the minute which i normally only get at night. On my modern radio its buried in noise. Big difference in sensitivity.