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Micky7850

LM307H Problem 65 2x12 Pi valve

Hi all,
Have been useing musicman amps for over 30 years now. Just got a 65 2x12 combo over here in uk. Decided to recap it for safety sake. On inpection one of the top hats was not seated correct in the socket. See Pic. Tried to move it around but no joy. Fitted another one,same thing. The amp is all original and has hardley been used over 40 years and in museum quallity. All i can think of is it was fitted at factory like that. Amp worked fine before so hopefully will do the same once i have recapped fully. Waitng for new 150Mf caps from mouser. Pics available

mgriffin155

Pin may have broken off

Hi Micky, A pin from an old IC may have broken off in the connector. If you have good eyes, a light and magnifying glass, take a look and see. I 'spect mm210 will see your post soon and give you the best advise for repair. Hang in there. -mgriffin

mm210
mm210's picture

I talked to "mickey" about

I talked to "mickey" about this but honestly, that's PROBABLY the best guess I've got too. Unfortunately, you MIGHT not be able to dig this out without damaging the socket. I've honestly never had to replace one but they are out there. Personally, I'd get a bulldog adapter, use THOSE pins to replace the round socket and adapt it to newer 8 pin IC's. The LM's are only going to get harder to find and the newer stuff is more cost efficient in the LONG RUN. (HHHHMMMMM-sounds like a good song title!) Just my 2cs worth. Mike.

Micky7850

LM307H

Hi All,
Checked pins on others and they were shorter so i have trimed the problem one and it seems to fit ok. Have some spare Lm307s and sockets but did not want too remove board. Hopefully after i finnish recapping it will be OK. Thanks to everyone for invaluable assistance,and may the site be longed lived. A big thankyou to you all. Micky

Micky7850

Lm307H MM 2x12 65

Hi All, Finnished recapping amp and putting it all back together, just like new again. Fitted all new JJs and biased at 21 ma per valve sounds great. Micky

mm210
mm210's picture

Good news indeed. Congrats.

Good news indeed. Congrats. Mike.

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