Not 50. More like 10-25. Mostly to cover my *** if mistakes in counting someone's board occurs.
We can do another order later if needed. There are plenty of boards that will be floating around.
Boards will be shipped after I get them. Hopefully less than two weeks. Last time they got hung up in customs. I assume they same will happen again, and possibly longer if a fee is leavied.
Feel like I am riding with my kids about twenty years ago... "Are we there yet daddy?"... "Now"... "How much longer"...
"Soon, soon, now don't make me come back there!!"
Then again, I guess it's easy for me to say as I listen to it
You asked for bigger pads, and updated labels. Well, everything you want, YOU GOT IT!.
Ha ha, I miss a decoupling cap at the output of 7812 ! Never mind, that one can go under the PCB ( from output to GND pin ). Please recommend this to the builders to avoid oscillation complaints. 100 nF MKT/ceramic caps or electrolytic 1 to 10 uF standard caps are OK. There is still space on the board for that cap but let's keep the PCB like it is now. Some of us tend to have nerve problems because of the waiting for the boards.
Thankfully there is a slight tiny miniscule error, otherwise it would be a perfect buffer and that's the last thing an audiophile wishes
Also the RK27 that was recommended by me to Ferds as a good standard potentiometer does not exist in 25 k or 20 k value. At least not the original Alps ones. So it will be 50 k log instead. I recall Nelson writing that higher ( than 25 k ) values can be used without penalties in the original B1. Maybe R3 and R4 should be lowered in value somewhat ?!?
If there is a wish for absolute perfection the text on the PCB could change too ( 50 k instead of 25 k ) but I think the boardhouse is already busy making the PCB's ?!
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BC517 solved the issue. So we skipped the comp cap placing. The 150nF is there in the BOM just in case. Was never on the 7812's output, it was across C,B, of the then relay NPN non Darlington driver. The 7812 100nF input decoupling I think I don't see in the BOM.
RK27 was the size guide. Depending on the source impedance it can even be the RK27 10k log. If above 20-25k, the input shunt resistors 220k, must be 10X the chosen pot's value. I would much prefer a switch pot around 20k. Also I see Alps blue 20k & Noble 25k vendored online. Just google.
You did not report on your proto build finishing. What is the story, did you finish and listen?
RK27 was the size guide. Depending on the source impedance it can even be the RK27 10k log. If above 20-25k, the input shunt resistors 220k, must be 10X the chosen pot's value. I would much prefer a switch pot around 20k. Also I see Alps blue 20k & Noble 25k vendored online. Just google.
You did not report on your proto build finishing. What is the story, did you finish and listen?
Please see the datasheet of RK27: there are no 20 k versions according to Alps. The standard decoupling cap for 7812 won't break the bank but it is a minor issue.
I am still gathering some of the parts. Got the MOSFETs. Got the K170. I have paired the LEDs but they are way over the desired values. And the (right) relays are not in yet. The K170 have to be matched too. Otherwise the board is stuffed and the case/enclosure is ready !
Mmm, I just found a different datasheet fom Alps indeed mentioning 20 k versions: http://www2.produktinfo.conrad.com/.../442771-da-01-en-Stereo_Poti_RK27112_100K.pdf
Sorry that I caused confusion but the datasheet at the Alps website only mentions 10 k, 50 k, 100 k etc.
I am still gathering some of the parts. Got the MOSFETs. Got the K170. I have paired the LEDs but they are way over the desired values. And the (right) relays are not in yet. The K170 have to be matched too. Otherwise the board is stuffed and the case/enclosure is ready !
Mmm, I just found a different datasheet fom Alps indeed mentioning 20 k versions: http://www2.produktinfo.conrad.com/.../442771-da-01-en-Stereo_Poti_RK27112_100K.pdf
Sorry that I caused confusion but the datasheet at the Alps website only mentions 10 k, 50 k, 100 k etc.
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At least we gonna see one in a case. Waiting for pics. DaveM may show first with a wooden one he builds.
I know about Alps datasheet I also know that I have seen Alps 20k in shops, online and in diy builds many times. I think its specially ordered option for some quantity limit. Anyway, Alps blue is smooth and reliable but opaque sonically. I would use an $5 carbon personally, or one like Grufti's. OK LDRs seem to be the thing next to a straight wire, judging from the grand bulk of diy reports, but it takes some involvement.
I know about Alps datasheet I also know that I have seen Alps 20k in shops, online and in diy builds many times. I think its specially ordered option for some quantity limit. Anyway, Alps blue is smooth and reliable but opaque sonically. I would use an $5 carbon personally, or one like Grufti's. OK LDRs seem to be the thing next to a straight wire, judging from the grand bulk of diy reports, but it takes some involvement.
Jonclancey, there should be some extra PCB's. Need to get all the originals delivered and shipped out first. There will be hynotizes available for sure. I will probably limit late orders to 1 or 2 pcb's to spread the product a bit.
I have put you on a want tab on the pcb spreadsheet I have.
I have put you on a want tab on the pcb spreadsheet I have.