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Old November 6th 18, 08:29 AM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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First recorded activity by RadioBanter: Jun 2007
Posts: 1,329
Default MFJ-259B touchup paint?


Does anyone know the paint color code (pantone?) or the name for the
paint used on the MJF-259B? No, I haven't called or written MFJ yet
because I'm lazy.

I'm rebuilding yet another antenna analyzer that was almost destroyed
by leaky alkaline batteries:
http://www.learnbydestroying.com/jeffl/MFJ-259B-repair/20181105_222734.jpg
I think I make it work again, but in its present condition, it looks
really ugly. Some of the aluminum was sufficiently corroded that I
might need some aluminum auto body filler before painting. If I can't
find the proper touchup paint (or a spray can), then I'll probably
just cover it in clear acrylic (Krylon) and be done with it.

PCB top view:
http://www.learnbydestroying.com/jeffl/MFJ-259B-repair/20181105_222750.jpg
I have a few bad guesses as to what the black spots on the tuning
capacitor might be. I'll probably need to sandpaper or wire brush the
cap.

PCB bottom view:
http://www.learnbydestroying.com/jeffl/MFJ-259B-repair/20181105_222823.jpg
The damaged area is mostly ground plane and should be easy to replace
with iron-on copper tape. This is what it should look like:
https://www.w8ji.com/images/MFJ259/259B%20align.jpg
As usual on the older models, I expect to find the ribbon cable
soldering to be mostly cold solder connections and 2 out of 4 input
diodes to be blown.

Incidentally, the owner of the MJF-259B has graciously allowed me to
use it for an experiment. I plan to replace the 10 AA cell battery
pack (15.0V) abomination with a 4 cell LiPo or LiIon battery packet
(14.8V) and an external charger. I'm also looking into a replacement
LCD display that has backlighting. I'll post the results when it's
done and hopefully working.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558