We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations. Always consult with the appropriate authorities if you have questions concerning what is permissable in your locale.

Author Topic: Cleaning circuit board in YB 400?  (Read 2733 times)

Offline IQ_imbalance

  • Full Member
  • ***
  • Posts: 220
    • View Profile
Cleaning circuit board in YB 400?
« on: June 22, 2015, 0343 UTC »
When packing up my YB 400 for a trip to the hills, I noticed that the alkaline batteries had corroded and left a fair amount of salt in the battery compartment.  I tossed the batteries, dusted out the compartment, and put new batteries in.  I used the radio all day Sat, and it worked wonderfully. 

Sunday morning, however, the bottom row of keys would only be recognized as "6", and the other keys were also jumbled up.  I opened her up and cleaned all the button contacts (finding a few flakes of salt here and there).  Put it back together and things are still wonky.  I suspect a bit of the battery salt has deposited somewhere I can't see, liquified in the high humidity, and is shorting something out.

I'm thinking a good cleaning of the circuit board might be the next step.  What are thoughts on using crc spray vs distilled water & isopropanol?  My thought is that distilled water would be the best at dissolving any leftover battery salt, but getting water off the board afterwards would be a pain (hence the alcohol)
LOG/NE-SW unterminated BOG
AFEDRI SDR-Net
Central MD

Offline IQ_imbalance

  • Full Member
  • ***
  • Posts: 220
    • View Profile
Re: Cleaning circuit board in YB 400?
« Reply #1 on: June 23, 2015, 0250 UTC »
Well and behold...it's working again.  Odd.
LOG/NE-SW unterminated BOG
AFEDRI SDR-Net
Central MD

Offline Pigmeat

  • DX Legend
  • ******
  • Posts: 3898
    • View Profile
Re: Cleaning circuit board in YB 400?
« Reply #2 on: June 24, 2015, 1923 UTC »
YB 400's and it's kid brother, the Grundig G5 are odd beasts. I've owned both. Sometimes you have to push the reset button and reprogram them when they lock up like that.

Offline redhat

  • DX Legend
  • ******
  • Posts: 1094
  • "It looks like green bacon in the sky"
    • View Profile
    • Email
Re: Cleaning circuit board in YB 400?
« Reply #3 on: June 24, 2015, 1948 UTC »
Isopropyl alcohol is probably the best, most of the other solvents can be rough on plastics.

+-RH
Somewhere under the stars...
WinRadio Excalibur/305 w/ a chi-town resonant loop, Kenwood KDC-U356 for mobile listening.
Please send QSL's and reception reports to xfmshortwave [at] gmail [d0t] com

Offline BoomboxDX

  • Hero Member
  • *****
  • Posts: 590
    • View Profile
Re: Cleaning circuit board in YB 400?
« Reply #4 on: July 26, 2015, 0617 UTC »
I've had good luck cleaning radio PCB's with tuner cleaner sprayed onto a Q-Tip.

Alcohol would probably work, too.

If your radio is turning off and on and such, it might be the battery terminals need to be cleaned, or hit with a bit of sandpaper or something similar to eliminate corrosion.

Also, sometimes the solder joint on the negative spring terminal can weaken. The spring can work the solder joint over time.

I had this happen on a DX398. The negative battery terminal's spring had weakened the solder point where the spring connects to the PCB. Easy fix. Just hit it with some solder, reheat the joint....

Good luck.
An AM radio Boombox DXer.
+ GE SRIII, PR-D5 & TRF on MW.
The usual Realistic culprits on SW (and a Panasonic).