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City: Dover, OH
Actually, my friend and I spent most of yesterday evening on this unit. He was wanting a challenge and I was bored, so off we went. Speaker cone was totally separated from the frame, so he epoxied that. In spite of using shims to keep the voice coil centered, it still isn't quite perfect and him and I both saw signs the spider might have been tampered with sometime in the past. Also, had to undo a 1950's or 1960's repair as we went. He worked on the chassis while I scampered for parts and tried to make sense of the Grunow capacitor code numbers in the Riders Manuals. Actually, this set is in both volume 7 and 8 of Riders, which is good because 7 had a badly printed page. It's home and back together now, but it will still need some tweaks. One thing I forgot to do was clean the band switch. Oops! It works, but is touchy. Also, the dial kept binding against the cabinet due to some sag in the chassis board, so I'll pull that and rework again. That said, this set really pulls in the stations on AM and is decent on shortwave. Sounds pretty good as well, though that speaker still isn't 100%. It's encouraging though and I figure some more tinkering will get this set up to 100%.
No matter where you go, there you are.
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City: Clayton, NC
Ronin: you have a metal 6L6 and what I assume is a glass 6L6 being driven by what appear to be either 6C5s or 6J5s.
Is that what your chassis calls for?
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City: St Louis MO USA
Posts: 2,023
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Joined: Jun 2010
City: Dover, OH
Hmm, yet another variant? One thing I wonder is: did all the variants use the same speaker? Also, I wonder why they switched to 6L6s? Mine pushes out a heck of a lot of sound with just the 6F6 tubes, though my friend thinks they might be getting pushed pretty hard. They do warm up pretty quick! I've had some radios that barely warm the 6F6 tubes and others like this one get them pretty hot.
No matter where you go, there you are.
(This post was last modified: 03-02-2014, 08:18 PM by Jayce.)
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City: Sandwick, BC, CA
I wonder if all versions of these had the same lousy band spread on short wave? Note how it goes from 5.5 to 18 mc on a single band, pretty much like the non Teledial Grunow that Bob Andersen has. In spite of this they used a sweep hand for logging, which seems almost like a waste of time. On my G.E M-83 they used five bands, longwave, broadcast, and three shortwave bands.
With regard to using 6F6s or 6L6 tubes as final outputs, that could be because of marketing, or simply because G.H.U managed to get a deal on 6L6 tubes in bulk. Apparently this was done with one of the brand Z models, they fitted the set with 6L6 outputs for marketing purposes, just to make it look like an audio "Hot Rod", but the 6L6s didn't do very much since the power supply didn't give them the extra B+ voltage they needed, just the usual 225-250 volts.
Regards
Arran
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City: Claremont, NH
Jayce,
I hope the measurements I provided will be of some help
YOUR WELCOME!
Gene
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City: Dover, OH
Thanks, Gene. Actually, thought I said thanks earlier, but I forgot. Sorry..
No matter where you go, there you are.
(This post was last modified: 03-03-2014, 04:56 PM by Jayce.)
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City: Dover, OH
Hey I just realized, Grunow copied Philco! This radio has an inclined sound board like my 116X! Hmm...
No matter where you go, there you are.
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Joined: Jul 2014
City: Bloomington, IL
Jayce,
I am working on a Grunow 1291 right now. I am looking for an operating manual for it so I can understand the teledial and the AFC. Were you able to find a manual for it?
Thanks,
Joe Miller
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