Hi all,
I am recapping my Fender 30th anniversary Blues Jr and ordered a new jewel(amber) to replace the red. Fender decided to make the red jewel enormous so a standard replacement wont fit the socket. Anyone have a work around? the light works fine, the hole in the cab is too big for the replacement though. cheers thanks
I moved recently and when I tried to play guitar through my Laney Cub 12 R I noticed it wasn't working properly.
The Problem: no sound. When I turn up the gain and the volume I do get some sound. Not nearly as much as it should produce though. I've dabbled with pedals and electronics and could D.I.Y. the repair. I wouldn't mind getting it checked and serviced completely either. However moving is expensive and if I can get it to work myself I would be happy to do that.
I'm guessing I need to check the tubes and get new ones. Can I check the tubes with a simple digital multimeter? Is it too dangerous?
Any tips?
Hi!
I have this Traynor YCV40 on the bench. The problem is that the high voltage is not reaching adequate voltage. Also voltage A-B or C don't change when switching the standby. Being not familiar with this power supply topology and all the switching, I'd like some help to understand better what is going on and have a better idea on what to troubleshoot first. Also, since it is a time consuming type of amp to work on, I'd like to get to the point without having to connect and disconnect over and over.
I get like 275V at voltage A with no tubes, and around 67V with tubes. I did try with known good tubes also, so I know it is not the tubes. I guess the voltage drop is just because there is just not significant amount of current in the circuit. Otherwise, I get about 440V on the right side of D7/D8.
I was told it's a 64. it has tremolo, but no tone control, and I can't find a schematic for a 10 watt skylark with tremolo and no tone control. Where should I be looking? Am I dense?
I bought a home two years ago. The previous owner worked for RCA for 40+ years. Electrical engineer. He left a bunch of equipment (and smaller doodads and whatnots). I do not want to throw it out, and I do not want to sell it on ebay. I wouldn't even know how to test them or ship them. If anyone is in the South Jersey/Philly area and would like to have a look, there may be a bounty of things in my basement you would be interested in. I understand they are worth some money but I'm not looking to get top dollar, I just want them to go to someone that will use and appreciate them.
I'm looking to level up in my sporadic amp building hobby and maybe start an amp repair/servicing side-hustle when I retire in a few years.
I'm thinking about building a resistor substitution box tailored for guitar amp designing, testing and tweaking.
My initial thinking is that this would have three independent resistor arrays, each with a rotary switch to change values. Physically it would look something like the mockup below:
Usage would be limited to low- medium power values:
Electrical limits:
To be clear, I'm not looking to build a decade box - each switch position would have a discrete resistor value and the switch decks aren't cascaded.
Before I get too far down the design rabbit hole I'm wondering how useful this would be in practice?
I work mainly on vintage tube radios and guitar amps. I recently got an oscilloscope for my bench. I understand that in order to protect the oscilloscope, it should be plugged into an isolation transformer. I am searching for an appropriate isolation transformer, but so far I've had no luck. It seems like on all the products that I look at on Amazon or other supply sites, someone comments that that product is not truly isolated and that you need to make a mod to it. I'd prefer to buy something that I don't have to mod. Anyone have any recommendations for me?
