HMV Radiogram 2346 Repair - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

ciaoflyer · 1st Jul 2020, 4:14 pm

Quote:

Originally Posted by Techman

Just do as I said and isolate the screens on all the AFs and the job's done. You can look into possible replacements should you have problems further down the line and need to actually replace them. I find that clipping or lifting the screen to each transistor cures the fault, although in theory a 'whisker' could actually short across the junction rather than just junction to screen, but this is very rare.

Thanks will deff try this!

ciaoflyer · 1st Jul 2020, 4:15 pm

Quote:

Originally Posted by Michael Maurice

No, you cant fit a silicon transistor in place of a germanium without modifying the bias conditions. In any case a BC transistor is for low frequencies like audio.

You can use these

Tried your link but it just came up with a search result?

AC/HL · 1st Jul 2020, 5:55 pm

There's a drawing of the transistor here. The wide spacing identifies the leads.: https://www.vintage-radio.com/repair...or-faults.html
There are other methods, search for tin whisker or AF11*, but clipping the screen lead is the easiest for a newcomer.

Michael Maurice · 1st Jul 2020, 6:35 pm

Quote:

Originally Posted by ciaoflyer

Quote:

Originally Posted by Michael Maurice

No, you cant fit a silicon transistor in place of a germanium without modifying the bias conditions. In any case a BC transistor is for low frequencies like audio.

You can use these

Tried your link but it just came up with a search result?

Try this link AF125

1st Jul 2020, 5:55 pm	#23
AC/HL Dekatron Join Date: Nov 2003 Location: Heckmondwike, West Yorkshire, UK. Posts: 9,642	Re: HMV Radiogram 2346 Repair There's a drawing of the transistor here. The wide spacing identifies the leads.: https://www.vintage-radio.com/repair...or-faults.html There are other methods, search for tin whisker or AF11*, but clipping the screen lead is the easiest for a newcomer.