I've getting a lot of hum from my wurlitzer 140b.

[zach]

I've been trying a few things, but I can't figure it out.  Any suggestions?
I've seen a lot of talk about the "reed bar" can cause noise.  What is the reed bar?
Thanks,
Zach

 

[zach]

These are the things I've done to try and fix the loud hum in my Wurlitzer 140b.

* I tested the speaker.
* I bought and installed a new wiring harness, with the led mod, from vintage vibe.
* I bought the amp rebuild kit from vintage vibe and replace a couple of resistors that were very hot.
* I used a file and filed the sides of the RCA input jack. (that seemed to help a little bit.)
* I noticed and reconnected a lose ground wire in the amp chassis.
* I replaced the wiring and connectors from the pick-up to the RCA input jack.

Just for reference the amp makes a loud humming sound with or without the pick-up input plugged into the RCA jack.

 

[abbey road d enfer]

These are the things I've done to try and fix the loud hum in my Wurlitzer 140b.

* I tested the speaker.
* I bought and installed a new wiring harness, with the led mod, from vintage vibe.
* I bought the amp rebuild kit from vintage vibe and replace a couple of resistors that were very hot.
* I used a file and filed the sides of the RCA input jack. (that seemed to help a little bit.)
* I noticed and reconnected a lose ground wire in the amp chassis.
* I replaced the wiring and connectors from the pick-up to the RCA input jack.

Just for reference the amp makes a loud humming sound with or without the pick-up input plugged into the RCA jack.

Not enough information to be really able to help.
Does the hum varies with the volume pot?

I don't know what a 140 is, I have a standard 200, but I guess it's of similar construction.
Reed is the accepted name for the blades that vibrate when being struck.
The reed bar is the large metal part that bears the reeds. IIRC there are two of them , one at the left and one at the right side.
It is also the signal ground. I would recommend that you check with a VOM if it's really well grounded. I think the ground connection is established only via the RCA connector shell.
The pick up is actually the large metal plate that goes all across the instrument (again I think it's in two halves). As such it is a big antenna for all sorts of parasitic signals. That's why there is another large metal shield that goes over it.