Recently I was browsing through Reverb as I do on occasion and stumbled across this little gem. Tried doing a little research on what the amp actually was or who made it, but could find very little detail on it. The price was pretty cheap, amp was in good condition however the seller said there was no output. I decided to make an offer and see what the story was on this little gem.
First inspection of the Amplifier
The amplifier arrived packed very well and was a lot smaller than I thought it was going to be. Tolex and chassis were in great condition given the age of the amp. Pulling the chassis out, there were no signs that the amplifier had any failures or has ever been services. None of the filter capacitors were showing signs of bulging or leaking. The power cord did have a bit of a fragile feel to the plastic, given its a two prong cord, its going to be replaced with a 3 prong power cord. Further inspection revealed that the amp did not have an inline fuse for the power, so that will be updated with a fuse as well.
Initial Power Up and Testing
Putting the amplifier up on the bench, first thing I test for before hooked the amp up to any speaker, is test for any DC leakage on the output. Also given the age of the capacitors, I made sure to put the amp on my current limiter in case something decided to fail when firing the amp up. Powering it up hooked up to a dummy load, I only saw about 100mv of DC on the output. So far so good. Hooked up the scope and signal generator to test for output. Nothing. There was a little noise on the output but nothing crazy. Turned up the reverb to see if there was anything from the power section. Still nothing. On a whim, I tapped around on the chassis a little and suddenly there was signal. I checked around for any broken solder joints but didn’t see anything that was a problem. Then when I moved the speaker plug on the back, I noticed that the tip was barely touching the tip on the speaker cable. The metal had fatigued from time and very flimsy. Out with the old jack and in with a good quality Switchcraft J11. Pots were pretty scratchy from dirt. A few flushings of Deox-It and the scratchness was gone but I didnt have any tremolo. I’ll have more to come on the amp as I try to trace out the circuit and create a schematic for it.
