[ARC5] BC-453B dial calibration saga.

[WA5CAB at cs.com]

If this is a typical BC-453-B or R-23 that has been through several hams 
hands over the decades, there is no telling whether it still has its original 
coil pack.  Try quickly aligning it at the two actual frequencies but do the 
alignment 10 KC high on the dial readings.  If that works, pull the dial 
locking pin, rotate and tighten the dial so that it reads right, and re-pin 
it.

On another (transmitter related) subject having to do with other pins, the 
flexible tuning shafts that connect the MO and PA tuning capacitors so that 
they change together are not interchangable transmitter to transmitter..  I 
recently brought home from Storage two BC-696's and two other transmitters 
hoping to make one good one for another list member.  I don't recall ever 
seeing these particular mods, and I don't know what they hoped to accomplish 
but one of them had the MO tuning capacitor completely removed (and the tuning 
shaft removed and discarded) and a 5-pin tube socket installed with a large 
non-military crystal in it installed in place of the original octal..  The 
other one had the tuning shaft between the two tuning capacitors removed and 
the MO tuning capacitor locked to a fixed frequency.  And a few other 
atrocities perpetrated.  I pulled the tuning shaft out of a third one and 
discovered that the two lock pin holes were over 0.060" longitudinally from both 
lining up at the same time.  So I had to re-drill the pin hole in one of the 
two capacitor tuning shafts.  Not an operation for the faint of heart!

In a message dated 07/27/2017 23:10:58 PM Central Daylight Time, 
magnuson at mac.com writes: 
> Hi, 
>    I'm still trying to get the dial reading to be a little more accurate.  
> The closest I can get on the 210 kHz alignment is about 216 with C-9 fully 
> unmeshed.  So I thought I would add a little more inductance to L-5 so I 
> could align to 210 kHz.  Now the closest I can get is 230 or so.  I 
> increased L-5 by adding a small ferrite core above the slug.  
>    Am I thinking wrong?  Comments?  Thanks.
> Skip Magnuson
> Spokane, WA

Robert & Susan Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480
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