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AnyFM tuner mechanics out there?

Perhaps  can shed some light on what's going on with my Mac MR 71?

Recently had the tuning dial cable restrung. Now I can't rotate the tuning dial to the right past 91.5! I can turn the dial all the way left. I popped the cover to inspect the cable, and don't see any obvious binding. For now I'm at least stuck with all the public stations I listen to.



Any idea what could cause the tuning mechanism to bind as described?
tablejockey
atmasphere's avatar
atmasphere
11,849 posts
 
There is a spring located on the actual wheel that is on the tuning capacitor shaft. Is it loose or does it have tension on it? It should be stretched out to be about 3/4 of the distance between totally loose and the limits imposed by the wheel. Take a look. You may have to tighten it up slightly.

Sounds to me like whoever did the restringing didn't fully test it out. Restringing is a bit of an art.
bdp24's avatar
bdp24
9,846 posts
 
For future work on your MR71, give Tom Carione at Brooks Berdan Ltd. in Monrovia (just East of Pasadena) a try. His fulltime job is as a maintenance technician at an L.A radio station (or is it a TV station?); he's in the shop on Saturdays.
tablejockey OP
3,920 posts
 
There is a spring located on the actual wheel that is on the tuning capacitor shaft. Is it loose or does it have tension on it? It should be stretched out to be about 3/4 of the distance between totally loose and the limits imposed by the wheel. Take a look. You may have to tighten it up slightly.

atmashpere-
I took a look at the wheel, and there are 2 springs. 1 is extended and the 2nd, not so much. 
https://www.manualslib.com/manual/1001212/Mcintosh-Mr-71-Fm.html?page=10#manual
The movement is fine for now, but I will drop it off for adjustment soon.
Thanks!

bpd24- Berdan was my first call when I initially had the restring. They were minimum 1 month lead time, as Tom does his thing every other week right now. Ended up going to George Meyer in LA(closer)they are a authorized Mac repair facility. Had an amp repaired there before. They did 2 week turnaround. Good service, kinda pricey(it is LA) At least the adjustment should be no charge!


atmasphere's avatar
atmasphere
11,849 posts
 
I took a look at the wheel, and there are 2 springs. 1 is extended and the 2nd, not so much.
@tablejockey  This is a pretty common setup. I suspect as you work it back and forth, the spring tension will equalize and it should be fine.
tablejockey OP
3,920 posts
 
atmasphere-
Thanks for the insight! The tuning seems fine after giving the dial a few turns across the spectrum.

I wasn't looking forward to taking it back to the shop and being without the great sound the Mac delivers.
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