SY said:Two pairs for me. Shall I PayPal you?
leadbelly said:I'll take a pair if still open.
No problem. Send an email to dsavitsk at ecp.cc and I'll send a PayPal invoice -- helps with keeping things organized.
I am expecting to receive these boards on the 4th or 5th, and I will send them out at that point.
Here is the start of some instructions. http://www.ecp.cc/d3a_exp.html Let me know if anything does not make sense.
Please look at the safety warnings -- use of these without taking precautions is really dangerous.
For now there are no extras.
Here is the start of some instructions. http://www.ecp.cc/d3a_exp.html Let me know if anything does not make sense.
Please look at the safety warnings -- use of these without taking precautions is really dangerous.
For now there are no extras.
I'm with SY on this one, in terms of linearity I haven't seen anything much better than the D3A.. I have used them in power amplifier designs and I use a pair in my phono stage where their noise performance is incomparable - never encountered anything this quiet..
And yes the transconductance can vary massively from one sample to the next, I have my stash of D3A all acquired for around $10 each and all are Halske and Siemens..
I'm also quite a fan of the 5842/417A a device which many have tarred with the same brush.
Doug, I am definitely interested in a board or two so sign me up if I am not too late..
And yes the transconductance can vary massively from one sample to the next, I have my stash of D3A all acquired for around $10 each and all are Halske and Siemens..
I'm also quite a fan of the 5842/417A a device which many have tarred with the same brush.
Doug, I am definitely interested in a board or two so sign me up if I am not too late..
No need to apologize. Thanks again for your effort.
I agree, you are saving all of us a lot of time. I know that it will be at least a couple of weeks before I can put the soldering iron to the board.
I realize now that I should have probably gotten one of these boards. Oh well. Still I have some other experimenter boards that I can try.
I recently picked up some 6J52Ps off ebay on recommendation from Wavebourne. He suggested they were like D3A's. I have some D3A's too, it would be neat to compare.
That reminds me I need a lab supply.
I recently picked up some 6J52Ps off ebay on recommendation from Wavebourne. He suggested they were like D3A's. I have some D3A's too, it would be neat to compare.
That reminds me I need a lab supply.
dsavitsk said:Domestic boards are in the mail. International ones will need to wait until Monday -- sorry about that.
No worries, that will give me time to think about what tubes to try them with (I have a new policy on not listing tubes on this forum, I have noticed how that is driving prices up; lets just say it's between a Russian tube and an NOS TV tube).
athos56 said:Got mine, they look great!
Yes, they do. Fine work, Mr. S! I like the small touches (like the provision for a chip resistor as gridstopper).
SY said:like the provision for a chip resistor as gridstopper.
Those are actually plate and cathode stoppers -- the grid stopper is full sized
JoshK said:Which chip resistors do you like to use for gridstoppers?
I don't have an opinion -- I like the ones that let me order 2 rather than 10. There is a little in MJ about SMD stoppers, so he may mention a specific type.
I have added some additional information on the website -- specifically some CCS details. Let me know if there is anything else I need to add.
Which chip resistors do you like to use for gridstoppers?
As stated the chip resistors are in the cathode and plate circuits. I usually use some generic 50 X 80 mil (0805) sized chip resistors that I got from a vendor sample kit for grid stoppers.
I may find time to build up one this weekend. I need to evaluate some tubes that are currently on the $1 list at ESRC. There are two weekends left in the $1 sale.
I plan to build a minimal configuration. Grounded cathode, variable negative grid bias from a power supply, triode mode, CCS or resistor plate load.
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