Using Peter Daniels boards, First Watt Schematic & CViller's One Channel Only BOM, I have some issues:
1. Schematic says that R21 & R22 are 10K. CViller's BOM says they're 22K. I bought 22K now. Anybody know why the change?
2. These boards are small. No problem. What is a bit scary, however, is the traces come to within a hair of each other at some solder points. Has anybody had any short circuits as a result of this?
3. What's R35 from the BOM? It's 33K, but not on the board or schematic?
Many thanks
Lucas
1. Schematic says that R21 & R22 are 10K. CViller's BOM says they're 22K. I bought 22K now. Anybody know why the change?
2. These boards are small. No problem. What is a bit scary, however, is the traces come to within a hair of each other at some solder points. Has anybody had any short circuits as a result of this?
3. What's R35 from the BOM? It's 33K, but not on the board or schematic?
Many thanks
Lucas
1. I think somewhere in this thread, Nelson commented that the 22K sounded marginally better.
2 Peter's boards do seem pretty dense. I have Cvillers boards so I haven't tried them. I guess they work.
3. R35 goes in series with the LED.
I appreciate these questions are a little tedious, but please bare with me.
I've been re-checking all of my connections and I cant see where the hum problem may be. I know this isn't safe, but I decided to quickly remove the safety earth lead from the IEC mains inlet (now reconnected) to see if it made any difference, and it didn't. Can you still have a hum loop with the safety earth removed?
I've been re-checking all of my connections and I cant see where the hum problem may be. I know this isn't safe, but I decided to quickly remove the safety earth lead from the IEC mains inlet (now reconnected) to see if it made any difference, and it didn't. Can you still have a hum loop with the safety earth removed?
Have you tried moving the tranny further away from the outputs?
I've had a Silchar tranny in an F5 that was noisy no matter where I put it.
The little Plitron's work well here.
Mine isnt hooked up yet, (grounds) power cords just temporarly clipped on. Silent as can be, it is virtually impossible tell if it is on.
Russellc
As far as the Daniels boards, Ive built 2 sets of them, shorts not a problem.
Russellc
Yes
Hum can be transferred over the air and moving transformers is the way to solve that issue.
It is also possible that the return currents for the signal input and the speaker output are mixed up somewhere. Among some possible solutions are improper star ground, RCA input jacks not isolated from chassis, high currents from speaker ground return flowing through the input ground loop, and safety earth connected to two different pieces of equipment which share a second ground connection, such as through interconnect cabling
It would seem you have already eliminated this last possibility.The way I connect my F5, the star ground is a point just after the main power capacitor. To this point are connected the speaker return wire, the main power ground from the power capacitors, and a thin wire that connects to the signal ground point on the PCB. I use Peter's PCBs, if that helps, but you can also connect the ground from the RCAs to the star.
I think you can. I think that the earth is still connected via your RCA's, no?
What he said ^
Hi Franz
You may...
It's silent when the input is shorted.
I'm currently amending Cvillers suggested layout and will post it when completed. If my error is easily spotted I will get the soldering iron out, but I would rather not wield the iron willy-nilly
What value would recommend?
I plan to make a DCB1 at some point. I remember Salas suggesting a 1uf cap at the input.
Is this the case with all 2SJ74 and 2SK170, or just the Toshibas? I understand your instructions until the very end, then the part about getting a new fet or something? I am getting ready to build with my new fets, you guessed it, Toshibas, so I'm trying to understand exactly what I need to do here.
Thank you,
Russellc