Building f-5 cviller layout questions?

[semi932]

I've populated two boards from the diy store with a kit bought elsewhere.

I know the parts are installed correctly except for maybe the pots for setting bias.

Is there a certain polarity for these?

Also I didn't install any thing in the led area as it's not necessary in my app.
Should this make any difference? Doesn't look like it to me.

I'm getting a dead short when plugging in one board with the dim bulb tester.
I know the power supply is ok as I tested it with a good 3886 board and everything is as it should be.

Can't find any mistakes on board and I have gone over it many times and all is correct.

Frustrating as I'm ready to hear some good sounds.

Any insight?

[Marra]

Regarding the trimmers you need to measure the resistance across R3 & R4; assuming they are the same as my cviller pcb's. Clockwise or anti depends on how you've installed them. Lots of info on all the other F5 threads.

[anilva]

Originally Posted by semi932

I've populated two boards from the diy store with a kit bought elsewhere.

I know the parts are installed correctly except for maybe the pots for setting bias.

Is there a certain polarity for these?

Also I didn't install any thing in the led area as it's not necessary in my app.
Should this make any difference? Doesn't look like it to me.I'm getting a dead short when plugging in one board with the dim bulb tester.
I know the power supply is ok as I tested it with a good 3886 board and everything is as it should be.

Can't find any mistakes on board and I have gone over it many times and all is correct.

Frustrating as I'm ready to hear some good sounds.

Any insight?

It is quite easy to get the pots right. Measure the pots across it's legs and the ohmmeter should read 0 (across one free leg and the other two which are shorted by the pcb), irrespective of how you have mounted them. Bulb will light up, if the pots are set higher...

[alazira]

Originally Posted by semi932

I've populated two boards from the diy store with a kit bought elsewhere.

I know the parts are installed correctly except for maybe the pots for setting bias.

Is there a certain polarity for these?

Also I didn't install any thing in the led area as it's not necessary in my app.
Should this make any difference? Doesn't look like it to me.

I'm getting a dead short when plugging in one board with the dim bulb tester.
I know the power supply is ok as I tested it with a good 3886 board and everything is as it should be.

Can't find any mistakes on board and I have gone over it many times and all is correct.

Frustrating as I'm ready to hear some good sounds.

Any insight?

The LED's aren't needed. It will help if you post a picture.

[semi932]

Originally Posted by anilva

It is quite easy to get the pots right. Measure the pots across it's legs and the ohmmeter should read 0 (across one free leg and the other two which are shorted by the pcb), irrespective of how you have mounted them. Bulb will light up, if the pots are set higher...

So if the bias is too high it will keep the bulb bright?

I'll recheck all and check this point.

[Woody1911a1]

see marra's post for how to check your pots

[qusp]

yep, there are actual physical indications of the direction, albeit under the board

[semi932]

Thanks for the help all.

Just the bias was causing my dbt to stay lit.

It's playing now at a low bias but it does sound great.

I've got a few more things to do with it before being complete but happy for now.

[Marra]

Originally Posted by semi932

Thanks for the help all.

Just the bias was causing my dbt to stay lit.

It's playing now at a low bias but it does sound great.

I've got a few more things to do with it before being complete but happy for now.

Congrats. Pics.

Sounds even better after a couple of weeks use.