Try this method, paraphrased from page 84 of the R-388 tech manual TM
11-854:
- Detach the drum cable from the drum pulley, but keep tension on it so
it doesn't slip off the bandswitch pulley which is down behind the front
panel.
- Set the band switch to the highest band (29.5 to 30.5 Mc)
- Turn the drum (and hence the drum pulley) about half a turn and hold
it against the tension of the spring.
- Run the cable up to the drum pulley (its front edge, closest to the
front panel of the receiver) and work it around the pulley one and a
half turns or more as required, before attaching the end to the drum
pulley. Now the drum should have the correct tension.
- Loosen the setscrew in the hub at the opposite end of the drum. This
requires one of those small Bristol wrenches. Align the drum so the
29.5-30.5 Mc scale shows through the window. Tighten the setscrew.

It might be good to have a helper hold the drum tension while you wind
the cable around the drum pulley.

FYI, TM 11-854 can be downloaded free of charge from
http://www.kg7bz.com/Manuals.html (thanks to August Johnson, KG7BZ).

73 & GL,
Joe K9LY


In article ,
(Yardleyite) wrote:

Has anyone ever fooled around with the band change drum/pulleys with the
Collins 51J/R-388 series of receivers? It seems I've acquired a 51J-2 that
the band is way off.