Dynatron Elan; transistor substitutes. - UK Vintage Radio Repair and Restoration Discussion Forum

Superhet Si · 29th Nov 2006, 9:25 pm

I have just purchased a Dynatron Elan for a measly sum of £1. Problem is, the set suffers some serious noise in the output stage. The fault seems to be coming from mainly TR5 which is a NKT 775

Never heard of it!

Could someone suggest an equivalent transistor please? Are these types any trouble?

ronbryan · 29th Nov 2006, 9:53 pm

AC127

Ron

Superhet Si · 30th Nov 2006, 10:14 pm

A BC107 works a treat. Total silence except for the wanted sounds!

ppppenguin · 30th Nov 2006, 10:20 pm

Quote:

Originally Posted by Superhet Si

A BC107 works a treat. Total silence except for the wanted sounds!

Which just shows how uncritical transistor subs can be. Beware that the BC107 is only rated at 100mA while I think the NKT775 is 300mA. If it works, doesn't overheat and runs at about the right collector current then it's fine. I mentioned collector current because the bias may need to be rather different for a silicon part.

Superhet Si · 1st Dec 2006, 7:53 pm

Thanks Jeffrey. The 107 seems cool and the radio sounds great. A realy nice warm sounding set this one.

29th Nov 2006, 9:25 pm	#1
Superhet Si Pentode Join Date: Jun 2006 Location: Crawley Down, West Sussex, UK. Posts: 151	Dynatron Elan; NKT transistor substitutes. I have just purchased a Dynatron Elan for a measly sum of £1. Problem is, the set suffers some serious noise in the output stage. The fault seems to be coming from mainly TR5 which is a NKT 775 Never heard of it! Could someone suggest an equivalent transistor please? Are these types any trouble? __________________ My Youtube channel https://www.youtube.com/user/simonspiers Last edited by Darren-UK; 4th Aug 2007 at 3:42 pm. Reason: Edited in accordance with Rule C1.

29th Nov 2006, 9:53 pm	#2
ronbryan Octode Join Date: Jan 2003 Location: Guildford, Surrey, UK. Posts: 1,959	Re: Dynatron ELAN AC127 Ron

30th Nov 2006, 10:14 pm	#3
Superhet Si Pentode Join Date: Jun 2006 Location: Crawley Down, West Sussex, UK. Posts: 151	Re: Dynatron ELAN A BC107 works a treat. Total silence except for the wanted sounds! __________________ My Youtube channel https://www.youtube.com/user/simonspiers

1st Dec 2006, 7:53 pm	#5
Superhet Si Pentode Join Date: Jun 2006 Location: Crawley Down, West Sussex, UK. Posts: 151	Re: Dynatron ELAN Thanks Jeffrey. The 107 seems cool and the radio sounds great. A realy nice warm sounding set this one. __________________ My Youtube channel https://www.youtube.com/user/simonspiers