Pars

Those things aren't film capacitors as he states in his ad are they? Electrolytic would be more like it.

I don't know from a gerber perspective, but could you save the soldermask layer as an image file and invert that using a graphics program?

That looks really nice John. A lot of planning (all the board and device holes, etc.). That doesn't appear to be a Modu case, and looks nice!

Michael, Check out the Rossman group videos on YouTube. He does a review of some hot air stations. He likes the Quick, but I believe he has one from Atten which is cheaper and performs just as well.

Found it (not the cartridge, but what it was). It was an Apature. I'm guessing it was a KOCE. Reading up on them, supposedly Ortofon made them or had something to do with them. I remember liking it though. Sorry to quote my own post, but somehow just ran across the brand of the cartridge today.

Happy Birthday Doug!

They do make another variant of that heatsink (2100G) which is not drilled/tapped, but I don't know if anyone stocks it. You could drill and tap that one for whatever reasonable fastener you wanted to use (4-40 or M3).

If you noticed in the datasheet, these are threaded for a 6/32 Imperial screw, which will not fit thru the insulator that you are using. I think most people use a longer screw with a nut/washer on the back (long enough that it is outside of the fins). Or use a 6/32 nylon screw with no insulator, but I don't know if that is verified to be tight enough or not.

Dukei (Mirko here) uses something similar to that. One of the reasons I ask is there is a difference in volume between modes (ZF is a bit louder), but more disturbingly, there is a slight image shift when switching between modes. I noticed this when using a 1khz test tone. The image shifts a bit to the left when moving to ZF. Per my previous question, the ZF resistor is the 1.9K resistor in the schematic and PCB? I assume so, but just wanted clarification,

Thanks Kevin. The ZF resistor is the one shown as 1.9K in the schematic and on the board (section marked Gain)?

@kevin gilmoreFor a CFP3, in SS mode, the gain is set by the 25K / 1.9K resistors? Or is it the 25K / 5K on the input? What determines gain in ZF mode? Thanks!

This is what I used. PNs missing for some stuff. Gilmore_protect3_mod_BOM_1.xlsx

Like I said, this isn't the exact amp I'm working on. The board on the right is a Gilmore protect board (HIGHLY recommended on one of these). The one on the left in this amp I believe is doing the SS/ZF switching.

This is an amp built by Mirko, that tkam bought from someone on HF I presume. The right channel was flaky, and since the builder is in the EU, he asked me if I'd take a look at it. It is in a single 2U 400mm Modu Pesante case. This isn't the exact amp, but similar.

Thanks Jose. I'm not having ground loop problems, but because of this differential in the grounds between the 2 PSUs (with one ground missing from the pot to the amp board) I was having the protector board trip (it was grounded to the other amp board). It doesn't look like the grounds of the amp boards or PSUs are tied to the chassis at any point either. The only ground connection between the R and L channels was at the pot. Reconnecting the ground on the pot seems to clear up the problem completely. I think I will run a ground wire between the output grounds on both PSUs.

I mentioned this in the dynahi thread, but after getting the input wiring fixed (cable jackets were putting too much pressure on the screw down terminals resulting in intermittent channel drop), I ran into another problem with the protect circuit tripping. It turns out that I had broken the ground connection at the pot of one of the wiper to amp cables. This connection is the only connection between the L and R channel grounds in the amp. The amp uses dual GRLVs, one per channel. Should I connect the DC grounds of the GRLVs to one another back at the PSUs? I'm thinking Yes. In this instance, I was seeing a DC offset of what appeared to be 36V, but that was dependent upon which ground was being referenced (which I didn't realize at the time). I found that when I ohmed out the input grounds between boards and it wasn't 0.

Yes, it is a cool device. I've been thinking about buying one for awhile now.

Question: when you do a dual mono amp, with a pair of GRLVs, do you connect the grounds of the two PSUs together? Asking because I ran into a problem on an amp. Offset on one channel jumped up quite high (tripped a Gilmore protect circuit). The pot ground on one channel had opened up from the pot to one channel board, and that was the only common ground point in the amp. I was thinking tieing the grounds together at the power supplies might not be a bad idea.

Happy Birthday Al! I hope you have a really nice one!

A couple of old T2 BOMs I have use a 71-CMF60-5M for the 5M resistor.

Thanks. I already had my own BOM for the CFP2. 2x that is missing the front end section on the CFP3, but should be more or less the same as an SS Dynalo for that portion.

I thought @luvdunhill had one, but maybe not? I assume the other forum is diyaudio?

Anyone have a CFP3 BOM? Excel spreadsheet preferred, but google or whatever is fine as well. Thanks!

Got it, thanks. I was trying to not disassemble it that far, so that is good to know.

Thanks. I guess one more thing to do on this thing Is that (paradoxper) who built this? Or was this one from Dukei?