[Heathkit] SB-102 drive belts

[Dick KF4NS]

Yea Drew, I agree. I have had the instruction for stringing the tune 
control since it came out in QST or H&K in the early 70's. Never got 
around to it for my HW100 because I heard stringing dial cord is not 
for the simple minded like me, hi,hi. Actually I wish there was a way 
to use belts with teeth on them.

Many time I have dabbed on some platen cleaner but that did not last. 
There needs to be a way to increase the friction by a significant 
amount. See, I keep looking for excuses for not using dial string. 
Hmmmm

NOTE: It is a must to keep the cap bearings lubed. I found out the 
hard way recently. I was able to free up the tight one with some PB 
Blaster. I was one of the lucky ones.

73, Dick KF4NS
St Petersburg, FL 33714 USA
Keep The Glow!


> From: "Drew P." <drewrailleur807 at yahoo.com>
> Sent: Wednesday, January 13, 2010 1:20 AM
> To: <heathkit at mailman.qth.net>
> Subject: Re: [Heathkit] SB-102 drive belts
>
> >
> > Jim Shorney wrote:
> >
> > "I reworked my HW-101 years ago to use string because I got tired
> of belt
> > slippage. I would stick with the dial cord, it's a better solution
> IMO."
> >
> > Paul Kraemer, who originally asked the question, seemed to
> indicate that
> > the preselector/driver tune control on his unit tends to bind at
> one end
> > of the travel.  If the binding is not in the tuning capacitors,
> then I
> > would suspect that the stringing job was done poorly or that there
> is
> > excessive runout in one or more of the pulleys.  Removal of the
> dial cord
> > and rotating each shaft in turn would soon confirm this.
> >
> > I don't know what size o-ring to use, but a piece of string
> wrapped in
> > belt fashion around the pulleys then cut to length could be used
> as an
> > o-ring selection aid. It is said that the plumbing section of
> almost any
> > hardware store would have suitable o-rings.
> >
> > I don't care for the rubber o-ring belts as used on my SB-101.
> They seem
> > to introduce a bit of backlash which makes tuning on 10 meters
> much more
> > touchy.  It could be that the belts have hardened with age and
> hence have
> > developed a "memory".  One of these days I will replace them with
> dial
> > cord.
> >
> > Drew