Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

37-650 Vernier Fine Tuning Mechanism
#1

Greetings!  I'm in the midst of restoring a very dusty but beautiful 37-650b (tombstone).  Only two bakelite caps left to go.  So far, working like a champ!  The issue I'm facing is with the fine tuning innards.  I'm not sure whether I just can't figure it out, or if there's a missing or broken part.  I've seen two different diagrams of how they're supposed to work, but neither appear to be a match for the parts I've extracted from the unit.  I've attached a photo of the parts laid out in the order I believe they fit.  There are six ball bearings.  One small, two medium, and three large.  I think the two medium-sized ones are supposed to be on each end of the spring, which fits into the coarse tuning shaft.  The three large bearings fit in the three holes of the coarse tuning shaft.  It's what's left that puzzles me.  If the small ball-bearing were somehow fused to the tip of the fine tuning shaft, I could see this working.  As it stands, the fine tuning shaft just spins, does nothing, and can be simply pulled out of the coarse tuning shaft.  Given the way it's shaped, it's really no surprise - there isn't anything to keep it in place.  Maybe it's simple, but clearly not simple enough for me.  I'm hoping to tap into the wisdom that I've seen answer so many other questions on this board (which have been invaluable in getting me to this point).  Any help would be greatly appreciated.  At this point, I'm desperate and looking to pick up another 37-650 chassis just to dissect it!

Stephen

   


Messages In This Thread
37-650 Vernier Fine Tuning Mechanism - by StephenB - 03-28-2015, 09:13 PM



Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM
First Radio restoration
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM
Zenith H725
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately. More ...EdHolland — 10:18 AM
Graphics for majestic 1050 dial glass.
Murf; I found this thread on the ARF, the first photo has a pretty good view of the dial glass. Regards ArranArran — 01:12 AM
Zenith H725
hello Ed, how about that speacial tape used for ducting it's like foil or how about thin piece of aluminum roof flash...radiorich — 12:19 AM
Zenith H725
Ed; One material that I have seen, but never tried for this was material for making exhaust gaskets, it's similar to ...Arran — 11:42 PM
Zenith H725
I just remembered, I have some hi temp silicone rubber material which could do the trick. Or a piece of FR4 laminate. Th...EdHolland — 08:39 PM
Zenith H725
The PSU filter cap arrived today (thank you USPS!) so I will work on that later. Meanwhile, I have the dial, speaker...EdHolland — 06:42 PM
Philco 610B oscillator wiring
Thanks Terry. After checking my notes I think I recorded about -10v at the 6A7 G4/control grid. The screen grid (G3 &...Tubester — 05:59 PM

[-]
Who's Online
There are currently no members online.

>