[Heathkit] What is a Harmonic Drive Part # 467-1?

[rbethman]

May 7, 1979 HW-100 Bulletin No: SSB Transceiver HW-100=22

Drive Slips or Doesn't Turn At All

The following is a modification of the HW-100 dial and VFO drive [PN 
467-1]. Replacement parts are no longer available. The customer who 
orders a PN 467-1 will receive the PN 969-48 parts pack and instruction 
sheet [PN 597-2065].

Parts required:

The following parts may be obtained by ordering parts pack [PN 969-48] 
which consists of: 1 - Vernier drive [PN 100-1041] 1 - Knob [PN 462-193] 
2 - Knob setscrews [PN 250-93] 8 - #3 Lock washers [PN 254-7] 8 - #3 
Nuts [PN 252-1] 2 - #6 Screws [PN 250-56] 1 - #6 X 3/8 Screw [PN 250-162]

Procedure:

A] Remove tuning knob and vernier drive assembly. B] Remove VFO and 
dial. C] Remove dial and hardward from VFO tuning shaft. D] Modify shaft 
and dial. E] Modify front panel. ((Tap holes for 6/32 machine screws, 
and enlarge hole to 1-1/8" using a chassis punch)) F] Remount VFO [Do 
not tighten mounting nuts] with dial installed on modified shaft. Dial 
must extend 1/4" in front of mounting plate. G] Install vernier drive 
[PN 100-1041] to modified front panel with two 6/32 X 1/4" machine 
screws [PN 250-56]. H] Align VFO into drive and tighten VFO mounting 
hardware. I] Tighten setscrews on new vernier drive. J] Install new knob 
[PN 462-193] with setscrews [PN 250-93]. K] Align VFO dial.

Note: modified drive will turn faster than original.


> Its a knob with a seperately rotating skirt but I'm missing the 
> intended application nor do I understand how it works!?!
>
> Carl
> KM1H
>