volume pot on 5F1 build question

telechamp · September 3rd, 2007, 08:36 PM

I want to first say, without lurking and reading all the posts on champ builds I would not have had such a fun time with the build. I found out the hard way not to run all the grounds to one location, I found out that if you don't connect all the lugs on the terminal strip you'll only ground a few things (that one was really funny when I found it). everything else went very well for the past 2 months. From the start I thought something may be up with the volume pot as it would be fairly loud on 3 with no increase in voulume until I would get to 10 thru 12 and at first when I would dime it it was really loud!
then as the days passed, the volume would drop to a lower level and some times after a 1/2 hour it would get louder. resently I can turn it on, get the good volume at 3 but nothing more, sometimes if I rotate the volume back and forth I can get more volume from 10 to 12 most of the time not. I have cleaned the pot, checked all my soldering, and even swapped tubes at first. When I use a MM on the pot and rotate it from off thru 12 I do not get any reading on my MM. would this be the indication that the pot is no good.
sorry for such a long post.

telechamp

JohnnyCrash · September 3rd, 2007, 08:47 PM

Welcome to posting on TDPRI!!!

You may have kept the soldering iron on the pot too long and burned it a bit.

You may also have the MM set incorrectly (or are using it incorrectly, what lugs are your probes on?). Are the lugs broken (can happen with a lot of solders and resolders)?

Finally, check your underboard solders to make sure they didn't drop out of the eyelets partially during any resoldering. Check for solid connections on the solders as well as "cold solders" (solder joints that are not shiney and silver looking).

A few final tidbits that pop into my mind:
1. Measure key voltages.
2. Check grounding lugs to make sure they are snug against the chassis.
3. Is the pot's far lug grounded?

If all else fails try replacing the pot with a spare and see if that works.

September 3rd, 2007, 08:36 PM	#1 (permalink)
telechamp NEW MEMBER! Join Date: Jul 2007 Location: surprise arizona Age: 54 Posts: 6	volume pot on 5F1 build question I want to first say, without lurking and reading all the posts on champ builds I would not have had such a fun time with the build. I found out the hard way not to run all the grounds to one location, I found out that if you don't connect all the lugs on the terminal strip you'll only ground a few things (that one was really funny when I found it). everything else went very well for the past 2 months. From the start I thought something may be up with the volume pot as it would be fairly loud on 3 with no increase in voulume until I would get to 10 thru 12 and at first when I would dime it it was really loud! then as the days passed, the volume would drop to a lower level and some times after a 1/2 hour it would get louder. resently I can turn it on, get the good volume at 3 but nothing more, sometimes if I rotate the volume back and forth I can get more volume from 10 to 12 most of the time not. I have cleaned the pot, checked all my soldering, and even swapped tubes at first. When I use a MM on the pot and rotate it from off thru 12 I do not get any reading on my MM. would this be the indication that the pot is no good. sorry for such a long post. telechamp

September 3rd, 2007, 08:47 PM	#2 (permalink)
JohnnyCrash Poster Extraordinaire Join Date: Mar 2005 Location: Lost Angeles and Orange County Posts: 7,128	Welcome to posting on TDPRI!!! You may have kept the soldering iron on the pot too long and burned it a bit. You may also have the MM set incorrectly (or are using it incorrectly, what lugs are your probes on?). Are the lugs broken (can happen with a lot of solders and resolders)? Finally, check your underboard solders to make sure they didn't drop out of the eyelets partially during any resoldering. Check for solid connections on the solders as well as "cold solders" (solder joints that are not shiney and silver looking). A few final tidbits that pop into my mind: 1. Measure key voltages. 2. Check grounding lugs to make sure they are snug against the chassis. 3. Is the pot's far lug grounded? If all else fails try replacing the pot with a spare and see if that works.