Re: Re: firing up but fuse blowing
The apparent resistance accross + - 24 / 0 is about 40-50Ohm for both channels, so I don't know whether a short would be. The voltage across R11 and 12 is 0 for both channel, but for left channel the current through +24 -24 is 0 and for right channel the current reaches 1.5A at when rail voltage is as low as + - 2 V.
Attached is picture of a mian board. I printed PCB layout on paper, pasted it on perforated board, and followed traces. I checked a couple times with oringinal schematics and can't find what is wrong.....
I'd appreciate any help!
cviller said:
The apparent resistance accross + - 24 / 0 is about 40-50Ohm for both channels, so I don't know whether a short would be. The voltage across R11 and 12 is 0 for both channel, but for left channel the current through +24 -24 is 0 and for right channel the current reaches 1.5A at when rail voltage is as low as + - 2 V.
Attached is picture of a mian board. I printed PCB layout on paper, pasted it on perforated board, and followed traces. I checked a couple times with oringinal schematics and can't find what is wrong.....
I'd appreciate any help!
Attachments
Re: Re: firing up but fuse blowing
LOL, CVILLER, how would you compare the sound of the F5 to your J-Fish? I'm afraid to admit I etched and stuffed your JFish boards, but still haven't connected them (2SJ109BL sitting there wasted).
The task that poses the biggest obstacle for me is drilling and mounting to heatsink, so after having all those problems lining up the output device holes for my F4 and A30 (6 per channel), I started to procrastinate but I did build an F5 (at least to running state).
RDK845: I'm sure you can already see this question coming but are you sure the back traces are not touching the heatsink?
cviller said:
If I had to get the boards manufactured, I might throw in another layer to reduce board size, but then the old farts in here might have troubles stuffing the boards.
LOL, CVILLER, how would you compare the sound of the F5 to your J-Fish? I'm afraid to admit I etched and stuffed your JFish boards, but still haven't connected them (2SJ109BL sitting there wasted).
The task that poses the biggest obstacle for me is drilling and mounting to heatsink, so after having all those problems lining up the output device holes for my F4 and A30 (6 per channel), I started to procrastinate but I did build an F5 (at least to running state).
RDK845: I'm sure you can already see this question coming but are you sure the back traces are not touching the heatsink?
and an other f5 pcb design 
Hello everyone,
Past few days i've been buzzy designing my own F5 PCB. Quite interesting because its the first time i really tried. I used DipTrace.
I'm wondering if anybody is willing to take a look at it. My main goal is it to make it the same size as Peter's F4 PCB's and locate the FETs on the same position so i can easily fit it in a F4 chassis.
few notes/questions:
- i intend to use cadock resistors in he signal path
- i want to have PCB's professionally made, that's why i used two layers (any suggestions where i can have a few samples made without paying the jackpot...)
- small traces are 1mm thick traces are 4mm. is this enough?
- does anybody know where i can get get those nice blue Panasonic .47r and 100r 3watt resistors in europe.. or does anyone have some spares i could buy?
thanks in advance!!
cheers,
c.
Hello everyone,
Past few days i've been buzzy designing my own F5 PCB. Quite interesting because its the first time i really tried. I used DipTrace.
I'm wondering if anybody is willing to take a look at it. My main goal is it to make it the same size as Peter's F4 PCB's and locate the FETs on the same position so i can easily fit it in a F4 chassis.
few notes/questions:
- i intend to use cadock resistors in he signal path
- i want to have PCB's professionally made, that's why i used two layers (any suggestions where i can have a few samples made without paying the jackpot...)
- small traces are 1mm thick traces are 4mm. is this enough?
- does anybody know where i can get get those nice blue Panasonic .47r and 100r 3watt resistors in europe.. or does anyone have some spares i could buy?
thanks in advance!!
cheers,
c.
Attachments
Re: Re: Re: firing up but fuse blowing
I think the sound of F5 is better than the jfish (babbelfish modified) and perhaps even better than the aleph j, but new toys are always more fun.
Your right channel appears to be shorted... try focusing on only one channel at a time - disconnect the right channel. Are you sure you haven't mirrored one of the channels?
twitchie said:
I think the sound of F5 is better than the jfish (babbelfish modified) and perhaps even better than the aleph j, but new toys are always more fun.
Your right channel appears to be shorted... try focusing on only one channel at a time - disconnect the right channel. Are you sure you haven't mirrored one of the channels?
cviller said:You are ok as well, but if you I have seen most people flip peter daniels boards the other way around.
stupid people
Thanks massimo, PM send!
i have decided i'm changing the the footprints of the ztx trannies, this footprint is asking for problems with my shaky hands
cheers,
c.
culture said:
stupid people
Thanks massimo, PM send!
i have decided i'm changing the the footprints of the ztx trannies, this footprint is asking for problems with my shaky hands
cheers,
c.
You should also consider making the holes for wire connections bigger, unless you have some fancy connectors.
Regarding the prototyping, you can try www.olimex.com/pcb/
Re: Re: Re: Re: firing up but fuse blowing
I have disconnected the left channel from PSU and taken out the right channel board from heat sink. It seems short on right channel is gone but now there is no current going through the board from + and - 24 rail. 10mA at 20V. there is no voltage across R11 and 12 regardless of P1 and P2 value. I replaced JFETs but the same results. Should I replace the Mosfets also? Except the bias voltage across R11 and R12, which voltage can I measure to see what's going on...
The left and right channels boards are identical looking from top.
Thanks for your help!
cviller said:
I have disconnected the left channel from PSU and taken out the right channel board from heat sink. It seems short on right channel is gone but now there is no current going through the board from + and - 24 rail. 10mA at 20V. there is no voltage across R11 and 12 regardless of P1 and P2 value. I replaced JFETs but the same results. Should I replace the Mosfets also? Except the bias voltage across R11 and R12, which voltage can I measure to see what's going on...
The left and right channels boards are identical looking from top.
Thanks for your help!
