Hope this thread gets a lot of play on the forum . . . but it is meant as an example for whatever electronics you may be working on . . it can be anything . . .
Got a Gibson Falcon tube guitar amp built around 1968-9. Got it for a song, around fifty bucks. Since it is getting into winter proper, I thought it would be a good time to work on it as a project while stuck indoors.
The person I got it from had gone into the amp to repair it, and what a mess he made of it. Hence the cheap price. The power supply section was completely bonkers. Fortunately, all three transformers (power, output, and reverb xformers) were tested and are OK.
Bought a complete set of Sprague 'orange drop' capacitors to replace all of the passive caps and a few silver mica caps to replace all of the old disc caps. Still looking at all of the resistors to see what needs to be replaced, but the ones in the PS section were all cracked due to the person who tried to fix it. The main filter cap had to be replaced too, since someone had replaced it with the cap with all of the wrong values.
I cleaned the pots, but have not otherwise tested them yet.
The connective wire used in these old amps are the cloth type; need to locate a source for it so I can rewire it too.
Had to replace the neon power indicator or 'pilot lamp'. It is in the mail to me ATM.
Had four of the six tubes (three 12AX7's and one 12AT7), so I ordered the two EL-84/6BQ6 to complete the lineup.
The amp also was missing its reverb tank and foot switch.
The speaker that came with it is a ceramic magnet 12"; but unfortunately it is a 4 ohm bass speaker. Not the original speaker. So I will need to hunt down an 8 ohm Celestion, Eminence, or Jensen brand speaker that has an Alnico magnet from that time period. Might be a little tough to get that piece; but there are enough other things that still need to be done in the mean time.
The amp cabinet had loose back cleats to hold the open back boards in place, so they were already re-glued and clamps/fixed. The rubber feet were worn out, so I installed a set of Fender bottom glides. The handle. grille cloth and vinyl box covering are all in good shape. But the back covers are completely missing, so I will need to fabricate those as well.
Sooo; what have you worked on lately?
Or what are you planning to work on?
Doesn't have to be radio related, but it helps . . .
Pictures are not mine, I found them on the 'net. But that is what it looks like:
Schematic of the amp
Got a Gibson Falcon tube guitar amp built around 1968-9. Got it for a song, around fifty bucks. Since it is getting into winter proper, I thought it would be a good time to work on it as a project while stuck indoors.
The person I got it from had gone into the amp to repair it, and what a mess he made of it. Hence the cheap price. The power supply section was completely bonkers. Fortunately, all three transformers (power, output, and reverb xformers) were tested and are OK.
Bought a complete set of Sprague 'orange drop' capacitors to replace all of the passive caps and a few silver mica caps to replace all of the old disc caps. Still looking at all of the resistors to see what needs to be replaced, but the ones in the PS section were all cracked due to the person who tried to fix it. The main filter cap had to be replaced too, since someone had replaced it with the cap with all of the wrong values.
I cleaned the pots, but have not otherwise tested them yet.
The connective wire used in these old amps are the cloth type; need to locate a source for it so I can rewire it too.
Had to replace the neon power indicator or 'pilot lamp'. It is in the mail to me ATM.
Had four of the six tubes (three 12AX7's and one 12AT7), so I ordered the two EL-84/6BQ6 to complete the lineup.
The amp also was missing its reverb tank and foot switch.
The speaker that came with it is a ceramic magnet 12"; but unfortunately it is a 4 ohm bass speaker. Not the original speaker. So I will need to hunt down an 8 ohm Celestion, Eminence, or Jensen brand speaker that has an Alnico magnet from that time period. Might be a little tough to get that piece; but there are enough other things that still need to be done in the mean time.
The amp cabinet had loose back cleats to hold the open back boards in place, so they were already re-glued and clamps/fixed. The rubber feet were worn out, so I installed a set of Fender bottom glides. The handle. grille cloth and vinyl box covering are all in good shape. But the back covers are completely missing, so I will need to fabricate those as well.
Sooo; what have you worked on lately?
Or what are you planning to work on?
Doesn't have to be radio related, but it helps . . .
Pictures are not mine, I found them on the 'net. But that is what it looks like:
Schematic of the amp
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