Recent content by hugh811

I think there is no significant problem with A step-up transformer from 120 to 220V. From a 50Hz wall outlet region to 60Hz region, also no problem. Your amp deliver 10W+10W, so power consumption (in theory) might be anywhere from 60-100W (please double check the specs of your amp), also not a...

Thank you all for your comments. I am happy to know that technically it will work. I will figure out how to fit it to specific projects.

OMG, now I look back, and just realize that these capacitors are quite big. My bad, assuming that they are as small as usual radial capacitors. My initial aim was to look for something of small size.

@ramjet : you said “other than their small physical size ratio to capacitance”. Do you think it has an negative impact?

Wow, the replies are beyond my expectation. Thank you all for your insightful comments. Indeed, i think these capacitors are not as small as smd components. But small enough to be built on a piece of circuit protoboard, which is to be mount beneath the chassis. And the original muti-section...

Hi everybody, I am very curious about eventual use of PP film caps as power supply filter cap in vintage tube amp. Then i cannot find the answer anywhere. Why that idea? Because some people say that now we have better technology, so much smaller caps now available. Some also said that film...

Hi, i think you should need a schematic. You will find it on the first page of this post. Q710 is a NPN transistor, if memory serves me well. Follow the instruction to test an NPN transistor. Are you sure that the left channel is "completely silent"? In my case, when I turn it on, it still...

500c deserves better caps than Teapo. In brief, 500c is a gem. I would grab it and pay a good price if volume pot and other pots are good, with all strong vintage tubes (not new production) and all transformers are original.

It makes sense.

In a vintage tube amp like 500c, originally there is none of them (radial lead caps). I prefer axial lead capacitors which look like this.

Radial lead cap looks like this. Basically it is dedicated for pcb (printed circuit board).

List of tubes (what brand, condition …) should be specified because these tubes count heavily in the final price. Upgrading tubes is very expensive, especially 12ax7 and the power tube quad.

Make sure that all tubes are there. There are many of them in this amp, especially small ones for radio section. Even if you don’t use the radio features, the tubes must be there, because they are part of the whole schematic.

I can see some critical caps and the rectifier have been replaced. But nobody can tell if it is “properly” done without a throughout checkups, measurements and some listening. The volume - and on/off pot seems original but i cannot tell if there is a problem with it. Esthetically speaking, i...

500C is a gem. Built like a tank, very good OPT, top quality original german capacitors. Attention must be paid to the volume pot which has a loudness tap. Quite expensive if you have to replace it. If sound is not even between the left and right speaker, the first culprit would be the volume...