[ARC5] BC-AN-229 Follies, part 3

[Ben Hall]

Evening all,

In part 2, I talked a bit about how I was cutting open and restuffing 
the original capacitors with modern units.

The recapping process continues.  I've got three more to do and they'll 
be done.  I did hit a stopping point the other night - this set was 
pretty modified when I got it.  Part of the mods involved removing some 
wiring and using some wires for other purposes compared to when it left 
the factory.

I've been replacing the wires as needed with modern wire with colors 
matching the wiring diagram.  The other night I noted I needed a length 
of red and I had none left!  So the electrical work was put on hold to 
let my order of wire get here.

So I moved on to some of the cosmetic problems:

First up was a general front panel clean-up.  Cotton swabs, paper 
towels, and some light cleaning has left it looking much improved.

Second up was filling in some of the unoriginal front panel holes. 
Metal tape went on the front panel and I filled in the holes from behind 
with epoxy.

Third up was the messed up left-hand side tuning cable connection.  It 
looks like someone in the past was trying to drill a big hole into the 
left-hand connection.  Why?  I have no clue!  But it left a big, ugly 
hole.  Out came the epoxy putty and with some "trowelling" I got the 
hole filled.  With some black paint, it will look presentable.

FWIW, the thread on the cable connection is 5/8"-27.  This thread 
appears to be common in the recording industry.  It appears that a 
replacement cap could be made from a cap made as an adapter for the 
recording industry like shown here by cutting off the 1/4-20 stud:

<http://r.ebay.com/oxfSp2>

While repairing the big hole in the left-hand tuning cable connection, I 
noted that the tuning had a lot of slop in it.

I removed the frequency readout dial and removed the cover to access the 
tuning capacitor gear and the tuning shaft worm gear.  In these radios, 
the tuning cable turns a worm gear that drives a large spur gear on the 
tuning capacitor shaft.  The worm gear shaft has a pair of thrust 
bearings - one on the outside of the set right behind the spline that 
the tubing cable would drive, and one inside the housing.  The "slop" in 
the thrust bearings is set by a length of hollow tube.  As this tube 
wears, the axial play in the worm gear shaft will increase.

To solve this, I drifted out the pins holding the left hand tuning shaft 
spline and the worm gear.  I drifted out the shaft from the left to the 
right, extracting it.  I cut a 0.003" shim washer from stock and 
inserted it between the inside thrust bearing and the length of hollow 
tube.  When put together, the axial play in the worm gear shaft was 
eliminated.  The sole source of play is now due to wear in the worm gear 
and tuning capacitor shaft spur gear.  :)

Having received my new wire, I'll return to recapping and electrical 
repair later this week.

thanks much and 73,
ben, kd5byb