Regency tr1-g - UK Vintage Radio Repair and Restoration Discussion Forum

Barnmead · 5th Dec 2007, 9:56 pm

I have recently been looking at one of these and found after replacing 3 of the 4 electrolytics and the signal diode that it will work if I attach an external aerial to the tuning capacitor.

Silence otherwise, though once or twice it worked for a few seconds after power applied with the internal ferrite aerial.

I am guessing that one or more of the transistors is warming up and gain going down? Or could it be something else?

I have no npn germanium transistors to substitute could I use a silicon one or has anybody suggest alternatives.

molochkartovski · 5th Dec 2007, 10:57 pm

These transistors wouldn't be AF117's would they?

Richard

Barnmead · 6th Dec 2007, 12:17 am

No, the transistors are colour coded 1956 vintage housed in oval metal cans with leads in line. Some of the earliest TI transistors. I believe one or more are type TI223. The output stage is pnp of same construction.

radiogammon · 6th Dec 2007, 8:12 am

Richard,

You can find a schematic for the TR1 at http://www.freeinfosociety.com/elect...ew.php?id=1924 . Have you replaced all of the ceramic cased electrolytics? In my experience, these are notorious for drying out with the capacitance falling almost to zero.

Barnmead · 6th Dec 2007, 1:48 pm

Hi John

Thanks for the website it looks interesting, though I have already the same diagram, which is for a TR1. Although similar in many respects the TR1_G has a npn output stage, additional resistors and a slightly different printed circuit layout to the TR1.

I found somewhere that the transistors in the TR1 are as follows:
TI223,TI222,TI222 and TI210

The first transistor in my set is a 2N172 the numbers on the others cannot be read unless I remove them.

As mentioned three capacitors have been changed apart from the one across the supply which is OK

5th Dec 2007, 9:56 pm	#1
Barnmead Pentode Join Date: Dec 2002 Location: Norfolk, UK. Posts: 168	Regency tr1-g I have recently been looking at one of these and found after replacing 3 of the 4 electrolytics and the signal diode that it will work if I attach an external aerial to the tuning capacitor. Silence otherwise, though once or twice it worked for a few seconds after power applied with the internal ferrite aerial. I am guessing that one or more of the transistors is warming up and gain going down? Or could it be something else? I have no npn germanium transistors to substitute could I use a silicon one or has anybody suggest alternatives. __________________ Richard

5th Dec 2007, 10:57 pm	#2
molochkartovski Tetrode Join Date: Jun 2005 Location: Wilton, Salisbury, Wiltshire, UK. Posts: 66	Re: Regency tr1-g These transistors wouldn't be AF117's would they? Richard

6th Dec 2007, 12:17 am	#3
Barnmead Pentode Join Date: Dec 2002 Location: Norfolk, UK. Posts: 168	Re: Regency tr1-g No, the transistors are colour coded 1956 vintage housed in oval metal cans with leads in line. Some of the earliest TI transistors. I believe one or more are type TI223. The output stage is pnp of same construction. __________________ Richard

6th Dec 2007, 8:12 am	#4
radiogammon Retired Dormant Member Join Date: Dec 2002 Location: County Down, Northern Ireland, UK. Posts: 275	Re: Regency tr1-g Richard, You can find a schematic for the TR1 at http://www.freeinfosociety.com/elect...ew.php?id=1924 . Have you replaced all of the ceramic cased electrolytics? In my experience, these are notorious for drying out with the capacitance falling almost to zero.

6th Dec 2007, 1:48 pm	#5
Barnmead Pentode Join Date: Dec 2002 Location: Norfolk, UK. Posts: 168	Re: Regency tr1-g Hi John Thanks for the website it looks interesting, though I have already the same diagram, which is for a TR1. Although similar in many respects the TR1_G has a npn output stage, additional resistors and a slightly different printed circuit layout to the TR1. I found somewhere that the transistors in the TR1 are as follows: TI223,TI222,TI222 and TI210 The first transistor in my set is a 2N172 the numbers on the others cannot be read unless I remove them. As mentioned three capacitors have been changed apart from the one across the supply which is OK __________________ Richard