The Amp Garage

Thanks. This is the schematic I'm working from. I've ordered LDR's.

How do I insert an image? I've tried and been unable to so far.

The power supply consisting of the 250-0-250 secondary, bridge rectifier, and 22uf reservoir cap, with no load came up at: 400 VDC. The center tap is unused. I dropped the Variac down to 30 VAC to reform the cap, just in case it degraded, as they have been sitting for about eight years. I'll bring t...

Thanks for the information. As is the case, I'll review it several more times. I'm just getting back into this after a 10 year break. I used to frequent Amp Garage and gained my knowledge of Train Wreck and Dumble amps. I already screwed up the power supply and have to redesign it. I used a full wav...

Thanks Sluckey. I was curious as to whether you were still with us. I didn't see an attachment feature and had tried the image insert.

Thanks again.

I'm not running FRFR cabinets. I'll try to insert the .png schematics here. To me, there are two separate channels that are combined after the EQ. The OD channel may be switched on or off. Here is the schematic: I'm having trouble uploading the schematic. I insert an address and the image does not l...

Initially I was going to build an amp based on the Fisher 500-s stereo iron. Too many problems as I didn't want to use the related output tubes. Anyway, along the path I decided instead to build the preamp section of a Soldano 30, up to the FX buffered output. My questions are: The clean and OD chan...

The direction has changed on the amp build. This thread is no longer relevant. I'll be opening a new Topic for the build. The problem was: I wanted to use 6L6 output tubes but the OT impedance was too high. I could have made the OT's work but there just wasn't sufficient power in the end unless I pa...

Thanks. For some reason I didn't get notification of your post. Anyway, I've been deep diving on this project. I may just use EL34's and reflect a lower impedance back to the primary. Looking at a Dirty Shirley style build. Sounds like a tuned JTM 45, on my modeler anyway. I've read the EL84 can get...

I've been away for years now. Okay, Someone gave me a Fischer 500-S stereo receiver that is in great shape. However, it is missing tubes and the strings that connect the tuning capacitors are broken, as well the AM ferrite antenna. The guts look fantastic as does the Iron. So, I figured I would buil...

I had built an amp that was working fine until I flipped the power on and off rather suddenly and the HT fuse blew. But so did one of the rectifier diodes. Took me a while to find the bad diode since it still read 200 ohms- in both directions. But that makes sense as the bias circuit I used was just...

I'll make some more tests this weekend. I will say I was monitoring the HV secondary and it began to come up with the Variac then the fuse blew out at 231 volts DC. After that it wouldn't even do that any longer. Nothing. The filament was flat dead. As I recall I measured the filament taps and they ...

I've completed an amp build and it's worked fine up to the other day. I turned the amp on and upon hearing the buzz of an unconnected input cable, shut it off, quickly plugged the cable in and then turned it right back on. It blew the fuse. I should add the amp is plugged into a Variac that was cran...

Why does it have to be a "Power Mosfet" as opposed to a signal level Mosfet?

silverfox.

So then it sounds like the wrong grid resistor could cause distortion and/or red plating depending upon which way the error goes. Too high a value, overheating, too low, distortion?

silverfox.