Transistor Subsitutes - UK Vintage Radio Repair and Restoration Discussion Forum

kernowcam · 28th Apr 2013, 9:37 am

I need a BFY51/CV7726 to do a repair.

Will a cv7746 be close enough?

julie_m · 28th Apr 2013, 12:01 pm

No, CV7746 is a PNP device.

2N3053 will substitute for BFY51, though.

kernowcam · 28th Apr 2013, 12:24 pm

I am going through Dads old stash of Transistors----
bfx88, cv9507, cv7746, bfx84, 2n1303, 2n696, cv8760, 2n2905, bfx88, cv9507, tix880

paulsherwin · 28th Apr 2013, 2:13 pm

The BFY51 is an old general purpose medium power transistor. Any NPN Si device with moderate gain and 1A current handling should be OK. The 2N696 is quite similar.

When subbing transistors you need to look at the transistor characteristics and the operating conditions of the circuit. If you aren't confident about doing that, you're better off sticking with the original components, especially if the transistor is likely to be operating at the limit of its ratings.

I get most of my transistor data from here.

28th Apr 2013, 9:37 am	#1
kernowcam Pentode Join Date: Dec 2011 Location: Camelford, Cornwall, UK. Posts: 188	Transistor Subsitutes I need a BFY51/CV7726 to do a repair. Will a cv7746 be close enough?

28th Apr 2013, 12:01 pm	#2
julie_m Dekatron Join Date: May 2008 Location: Derby, UK. Posts: 7,735	Re: Transistor Subsitutes No, CV7746 is a PNP device. 2N3053 will substitute for BFY51, though. __________________ If I have seen further than others, it is because I was standing on a pile of failed experiments.

28th Apr 2013, 12:24 pm	#3
kernowcam Pentode Join Date: Dec 2011 Location: Camelford, Cornwall, UK. Posts: 188	Re: Transistor Subsitutes I am going through Dads old stash of Transistors---- bfx88, cv9507, cv7746, bfx84, 2n1303, 2n696, cv8760, 2n2905, bfx88, cv9507, tix880

28th Apr 2013, 2:13 pm	#4
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,947	Re: Transistor Subsitutes The BFY51 is an old general purpose medium power transistor. Any NPN Si device with moderate gain and 1A current handling should be OK. The 2N696 is quite similar. When subbing transistors you need to look at the transistor characteristics and the operating conditions of the circuit. If you aren't confident about doing that, you're better off sticking with the original components, especially if the transistor is likely to be operating at the limit of its ratings. I get most of my transistor data from here.