UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

Radio Wrangler · 5th Aug 2018, 12:09 am

Early RP25 had germanium transistors in the IFs and the AM front-end
later RP25 changed to lockfit silicon transistors in the IFs and AM front end
RP25B was a step further to an IC in the FM section. And also as said before, the plain dropper resistor was changed to a transistor regulator.

The RP35 Herald followed the change to silicon and used the same AM IF boards as the RP25 family. Just this afternoon, I had to dig into the RP25 manual update section in order to repair a late Herald.

David

5th Aug 2018, 12:09 am	#4
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,876	Re: Hacker Sovereign models. Early RP25 had germanium transistors in the IFs and the AM front-end later RP25 changed to lockfit silicon transistors in the IFs and AM front end RP25B was a step further to an IC in the FM section. And also as said before, the plain dropper resistor was changed to a transistor regulator. The RP35 Herald followed the change to silicon and used the same AM IF boards as the RP25 family. Just this afternoon, I had to dig into the RP25 manual update section in order to repair a late Herald. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done