diytube.com

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... K:MEWAX:IT

Is the above more or less plug-and-play, provided you BYOT's (bring your own transformers) and (bring your own tubes)?

What driver tubes did they use? Was this circuit any good? Just curious.

Those used a 6GH8 driver tube. The driver circuitry is basically the stock old ST70 with larger coupling caps.

This has given my business partner an idea :-D

Cheers!

1. An ST70 driver board replacement exactly like the original except for 6gh8 or 6u8's?

2. A drop-in pcb replacement board that DOES fit the classic ST70 chassis to include the output tubes being on the pcb also?

3. ?

tomlang wrote:2. A drop-in pcb replacement board that DOES fit the classic ST70 chassis to include the output tubes being on the pcb also?

Neat idea, but isn't it a lot cheaper to make a smaller PCB and just use chassis mount sockets? What does the bog honkin' board really get you?

Yeah, modular would be better.

The shape a PCB would have to be to be a one-board-drop-in would be such an odd shape, there would be waste. Far too expensive and you're locked in on one type of driver/output.

Now if we made them modular, you could swap drivers and output boards at will. With appropriate iron and PS board, you could go from EL34 to 6L6GC to KT66/77/88, etc.

A configurable amp! :-D

Cheers!

tomlang wrote:1. An ST70 driver board replacement exactly like the original except for 6gh8 or 6u8's?

Sound Valves made an st70 clone called the "Vta-70i Amplifier", which has a driver board like the one pictured on the ebay auction.

http://www.geocities.com/rikblank@swbel ... TA70i.html



They also made the driver board for the Dynaco (Panor) ST 70 series II.

http://www.tnt-audio.com/ampli/dynaco1e.html

From what I can tell, they also made an upgrade driver board for the original Dynaco st70.

The boards are similar in design, but they do not have the identical circuitry. I cannot find a schematic for any of them.

2. A drop-in pcb replacement board that DOES fit the classic ST70 chassis to include the output tubes being on the pcb also?

I do not know what board is being peddled on ebay. It could be any of the above 3. It may fit; It may not.

Nice Drake ham radio gear in the background!

73 de KB1MZ

Apparently since Yahoo has taken over Geocities web sites are going bye-bye before the end of the month.