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Messages - solderer25

I have the schematic for this amp if that will help you. The slave output jack which you are looking to modify does indeed connect one of the speaker terminals to ground. The connection between these terminals breaks when a jack plug is inserted hence silencing the speaker. As g1 has pointed out, just short out the relevant terminals with a length of wire.
Schematics and Layouts / Re: Pignose amp?
November 03, 2020, 05:35:34 PM
If the socket is broken inside you will most likely have to replace it. I believe Fender used a similar part on many of their amps. The Champion 110 model I have uses one. If you contact Fender there is probably a part number for it. Failing that you could probably replace it with a standard stereo jack socket.
Most SS Fender amps have a great clean sound IMHO. I have a little Champion 110 which really sings. I would steer clear of Peavey. Great amps, but even the clean channels seems to have a bit of dirt on them, to my ears. I used to own a small Sound City practice amp. It was only a few Watts, but had a nice elliptical speaker of decent size. The clean on that amp was to die for! Worth picking up if you can find one.
Schematics and Layouts / Re: Frontman 212r
February 18, 2019, 03:00:19 PM
I had a similar problem with a switch I ordered for a Marshall amp. The pins were a slightly smaller footprint so I carefully bent them outwards to make them fit. With a little bit of fiddling I was able to line up the switch plunger with its intended hole in the front panel - job done.
The Newcomer's Forum / Re: Amp repair?!
January 29, 2019, 06:51:56 AM
Hi. I would return and check the bridge rect. and smoothing cap for the heater supply before suspecting the transformer. These can both be easily tested with a DMM. Check also the solder connections for both as problems there could also give the symptoms you are having with heater supply overvoltage. The design of this part of the circuit really is primitive - cost cutting gone mad!
If an amp has been left in storage unused for a long time and gives problems when fired up again I always spray all moving parts with contact cleaner spray. So that means all jack sockets as well as switches and the control pots (e.g. gain, volume, tone controls). Damp air gets in these parts and oxidises the contacts - the resulting pops and crackles (and also hum) are a sure sign of this. If this does not cure the problem then we have to delve deeper.
Amplifier Discussion / Happy New Year!
January 09, 2019, 03:04:41 PM
Just like to wish everyone on SSG forum a very Happy New Year.
There are many useful sites of information on the web and this is definitely one of them.
Newcomers are made welcome and even simple questions/requests are responded to with considered and knowledgable replies.
Please keep it that way!
We all had to start somewhere so lets keep making that learning journey fun.
I am talking about the lower of the two 2N3773 output transistors. If it was myself working on the amp I would first remove all the connections from this tranny and do a resistance check across the B/E terminals. If it reads zero on resistance range that is your problem (or one of them!) and the device must be replaced. Hope this helps anyway.
From your readings I would suspect Q2 is faulty as there should be about 0.6V DC difference between the B and E terminals. To me it looks like internal dead short between base and emitter. I would replace Q2 anyway on that evidence.
You need to find out which component/s is/are getting too hot. If it has two or four output transistors (usually bolted to the back panel or a heat sink) and these are getting hot then it may need rebiasing. There is usually a small variable resistor (preset) somewhere on the
circuit board to adjust this. Warning - do not attempt to do this adjustment unless you have suitable experience with electronics. You could do more harm than good if you start adjusting things ad hoc.
Hi. Proceed with caution if you suspect a wrong pinout with a transistor as many of them come in different packages. The BC212 for instance, has a different pinout to the BC212L. My data book shows this transistor comes in three different packages, depending on the last letter (or letters) of the type code.
"If I am not mistaken, the heatspreader has tabs that solder to the ground tabs."
Better not try and pull it off then - my mistake sorry.  xP
Hi. The copper coloured thing is just a heatsink and is clipped on to the IC. It should just pull off. Probably some white heat conducting paste between it and the IC as well. Do not be tempted to scrape this off as it helps heat conduction if IC is found to be ok.(IC = chip!)
Hi. I am following this thread with interest as I too have a mains/battery Escort amp. I dont recognise the schematic posted previously though. The Vox Escort circuit I know uses a single transistor preamp and an old school TBA810 power amp chip. If the TBA810 is found to be duff it can be replaced (still available mail order I think) but is tricky to desolder/solder as the pins are staggered.
The Newcomer's Forum / Re: Orange Crush 12 repair
April 14, 2018, 02:51:59 PM
You dont need to worry about discharging caps as voltage across them not large enough to be a hazard in small SS amps. Just make sure amp is unplugged when you delve inside. To clean pots, get hold of some contact cleaner spray (Servisol or similar - not WD-40!) Fit the small tube (looks like a straw) into the nozzle and spray for a second or two inside the pots. There should be a small vent hole in the body of the pots into which you poke the tube and spray. Give the jack sockets a blast while you are at it. This is best done by inserting a jack plug to open the spring contacts before spraying. Good luck.