Will your M25/Sissysit boards eventually be offered with these modifications on the board?
If so, or maybe even if not I am inclined to build M25, (proven stable without mods) which is what my kit was for initially. I would buy transformers and power supplies as if building mono blocks, reserving transformer and one supply for eventual Sissysit build.
At that time, buy additional chassis, use reserved transformer and power supply and convert them to half M25, haif Sissysit with switch to shift power supply to one board (M25) or the other (Sissysit) like another member did with his M2 and Aleph J.
Many advantages (mono block configuration) and only one disadvantage I can think of, not being able to use both different amps in two different systems. Heaven knows I have a spare amp or two.
But, before I buy another set of boards, will they be available with these mods on boards, or will this always be add on? If always as add on, will build Sissysit first.
Thanks,
Russellc
One other question, at risk of once again demonstrating the depth of my not understanding.....
I have two matched sets of the required sits from Prass. Does this amp function with 2 sits on each side, rather than sit/mosfet mix, or (as I assume) the magic in the mismatch? (not to mention the special tidbits and opto workings)
Why I would do this I have no idea, just popped into mind when Zenmod was discussing nature of mismatch (between mosfet and sit) causing bias drift upwards, and how M25 didnt do this.
Ouch,
Russellc
I have two matched sets of the required sits from Prass. Does this amp function with 2 sits on each side, rather than sit/mosfet mix, or (as I assume) the magic in the mismatch? (not to mention the special tidbits and opto workings)
Why I would do this I have no idea, just popped into mind when Zenmod was discussing nature of mismatch (between mosfet and sit) causing bias drift upwards, and how M25 didnt do this.
Ouch,
Russellc
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The SissySIT needs opposite sex devices, so does M2 (M25). The F6 uses same sex devices. So that may work if you can figure out the bias, etc.
Rush
I was so focused on the sit/mosfet difference I forgot about opposite sexes!
Will wait for zenmod for possible board change in the future.
Russellc
ZM,
I was reviewing the schematic in post 1500 and it only has one 100R resistor. Do you remove the resistor from the SIT or does it stay in place?
I was reviewing the schematic in post 1500 and it only has one 100R resistor. Do you remove the resistor from the SIT or does it stay in place?
twitching,
I got that, but the original schematic shows R21 as 100R and 100r on the flying lead. It is not on the schematic in post 1500
I got that, but the original schematic shows R21 as 100R and 100r on the flying lead. It is not on the schematic in post 1500
everything stays the same for existing pcbs , and little pic tutorial is going to be posted in few days , taking care of existing parts nomenclature
schmtc from post #1500 is a guide , and if one is confused with it , simply ignore it
regarding SIT gate resistor - in general - if wires are short between SIT gate and pcb , gate resistor (100R) can be placed on pcb
if wires are of liberal length , use 0R in place of pcb gate resistor and add fluying gate resistor , soldered at SIT gate and heatshrinked with wire
one can use both , in praxis , without too much thinking ........ and problem could arise only in case of leaky SIT gate ........ when problems are there , anyway
schmtc from post #1500 is a guide , and if one is confused with it , simply ignore it
regarding SIT gate resistor - in general - if wires are short between SIT gate and pcb , gate resistor (100R) can be placed on pcb
if wires are of liberal length , use 0R in place of pcb gate resistor and add fluying gate resistor , soldered at SIT gate and heatshrinked with wire
one can use both , in praxis , without too much thinking ........ and problem could arise only in case of leaky SIT gate ........ when problems are there , anyway
yes
finally finished with shipping stint , sorted few everyday life things , so I can proceed with workshop activity
expect it in day or two
oh yes, having some tiny wires to solder these days too , but I'll manage
finally finished with shipping stint , sorted few everyday life things , so I can proceed with workshop activity
expect it in day or two
oh yes, having some tiny wires to solder these days too , but I'll manage
SissySit cooking, I seem to have same drift problem also. Guess I have to take case open once again 😀
Hmm, this is weird. When fridge compressor turns on, dc will be 40mv off. When baking oven is on, dc will jump 100mv off. Turn everything off and there we go: stable dc offset.😕
which means - you have lousy mains
remember that SIT is not nicely behaved part when rail is going up or down
sole solution is - regulated rails ..........
and I don't like that ...... besides - resulted DC offset drift is small enough for me not to worry
change phase for your FiFI gadgets ...... try to find one free of Cousine
remember that SIT is not nicely behaved part when rail is going up or down
sole solution is - regulated rails ..........
and I don't like that ...... besides - resulted DC offset drift is small enough for me not to worry
change phase for your FiFI gadgets ...... try to find one free of Cousine