PL700B Meter sticks on zero FIX

[premiumplus]

Hey Guys,
By request I documented my repair of my PL700B sticky Dixson meter today. Here's what I found:
Disassembed the meter and found that the meter stop on the left was allowing the meter to swing too far to the left, so the meter would hang up in that position.


When you take the meter face off, be careful. The two meter stops are held by the two screws that hold the face on, and they'll fall off.

Here is what the meter stops look like out of the meter...

After inspection I found nothing wrong with the meter movement, and decided to reassemble it and just move the stop a little bit to the right to make the meter zero just a hair higher than it had been. It was going so far to the left that the movement was hanging up. Moving the stop very slightly to the right cured the problem.
A little sticky-tack on top of the standoff holds the meter stops in place while I put the face back on and insert the two screws. Great stuff, sticky-tack...


Meter reassembled and ready to reinstall in the amp faceplate. Success.

 

[laatsch55]

Thank You Dave, that has not been down to date>>><>

 

[NavLinear]

Thanks Dave - another great job with the repair. How hard was it to realign them and to get that slight adjustment to get a better meter movement? It seems somewhat tricky getting those stops back in place and orientated correctly.

The sticky tack wasn't white so what is it?

 

[Northwinds]

Ha! I have both meters in my PL400 that won't go below the 20+ mark unless I tap the shit out of the bezel area. Got an idea how to fix them? Jer's hair may have grown back by now but he worked at them for awhile when he had the amp and did not have much luck and that must have been frustrating. It would be nice to have a set that worked correctly again. From 20+ on up, they work fine. I just wonder how much they are actually "off" other then not returning to normal with no source going. I have not flattened them to the right... yet hehehehehheeee but have had them swinging in the red a few times recently and the amp seemed to want to deliver more goodness but I chickend out. Actually, the wife's glare sort of quelled the desire LMAO

 

[premiumplus]

Thanks Dave - another great job with the repair. How hard was it to realign them and to get that slight adjustment to get a better meter movement? It seems somewhat tricky getting those stops back in place and orientated correctly.

The sticky tack wasn't white so what is it?

It was easier than you might think, the hard part is not overdoing it. The white you see is a piece of tubing that is slid over a hair thin wire connected to the brass washer. It's tiny, probably smaller than 1/64". When I reassembled the meter I used a little blue sticky-tac to hold the washer/wire/tube meter stop assembly in place long enough to get the face plate in position and put in the two screws. An added bonus of the sticky-tack was that I could rotate the meter stops to where they needed to be before I tightened the screws. I had to form the wire a bit to make it line up with the needle pointer, but you just need to be gentle. I used a jeweler's screwdriver to form it as needed. Then you can move the meter about by gently blowing on it. I never touch the pointer directly if I can avoid it, I've destroyed more than one meter by ruining the jewel bearings. They're really fragile. A good magnifier light and steady hands help lots...
I should mention that it is CRITICAL to NEVER BEND anything like this. Only FORM it. This is something I was taught years ago when I was learning to repair mechanical adding machines and other office equipment. Form, never bend...

 

[premiumplus]

Ha! I have both meters in my PL400 that won't go below the 20+ mark unless I tap the shit out of the bezel area. Got an idea how to fix them? Jer's hair may have grown back by now but he worked at them for awhile when he had the amp and did not have much luck and that must have been frustrating. It would be nice to have a set that worked correctly again. From 20+ on up, they work fine. I just wonder how much they are actually "off" other then not returning to normal with no source going. I have not flattened them to the right... yet hehehehehheeee but have had them swinging in the red a few times recently and the amp seemed to want to deliver more goodness but I chickend out. Actually, the wife's glare sort of quelled the desire LMAO

Northwinds, check and make sure that the meter face hasn't moved and is causing a bind on the meter pointer. I've seen these things put together with Scotch tape (no kidding) and it dries up over the years. Sometimes they use double sided tape...same problem.
Something is binding those movements...

 

[mlucitt]

Make sure the meters are grounded properly. If not, static electricity can cause the readings to be off. If you wipe a dry rag across the front of the meter you will see what I mean. All this assumes there is no mechanical binding.

Oh, and definitely, keep the meter pointers in the red at all times, right Lee?

Mark

 

[laatsch55]

Absolutely, meter zeroing is not near as critical that way...

 

[Zach C.]

Turns out this is going to be a timely thread for me, since my new PL400 has a sticky meter.

Clearly, they're not the same meter, but I'm guessing/ hoping this will be instructive when I tear into it.

thanks,

Zach

 

[laatsch55]

Ya might be surprised....

 

[Zach C.]

Ya might be surprised....

Same, only different?

 

[laatsch55]

Exactly... you're quick lad.....

 

[Zach C.]

Exactly... you're quick lad.....

Good to know.

 

[Zach C.]

Good to know.

You're not getting into my pants that easily, buddy!

Z

This was intended as humor, but apparently I missed my target.

Zach

 

[NavLinear]

This was intended as humor, but apparently I missed my target.

Zach

I thought it was funny!

 

[laatsch55]

I was laughing to hard to post for hours!!!

 

[Zach C.]

I was laughing to hard to post for hours!!!

I'm sorry. I didn't meant to get you that worked up!

 

[laatsch55]

One for every occasion. That was Jer's pet peeeve, didn't like the limited selection on other forums..