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Old 08-19-2018, 08:14 PM
Electronic M's Avatar
Electronic M Electronic M is offline
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Transformer for record cutting head

Many years ago I bought a Wilcox Gay Recordio model 6B30. Around 10 years ago it was mostly working on its original caps, and I recall putting into record mode and the record cutter needle vibrating with the audio input then suddenly not. It is finally getting a recap, and it seems the transformer for the cutting head is open. Does anyone know what it can be replaced with? Is it just a speaker transformer, or is it something special?

Riders doesn't give a part number. The original has 81 2096 on its frame.
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Old 08-20-2018, 01:09 PM
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benman94 benman94 is offline
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That model should use a crystal cutting head; I'd bet your output transformer is fine, and it is actually the head that is defective. They're about as unreliable as a crystal pickup...

Does this model drive the cutting head from a 6J5 or 1/2 6SN7?
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Old 08-21-2018, 01:24 PM
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I found a listing for a Wilcox-Gay 6B10 on eBay in Maryland, although such units are obsolete; the one listed may have been found in an estate or some such. If you can get this one it may have the record cutting head you need to fix yours, although I don't know what you would use the record cutter for these days since the blank discs aren't available any longer, among other things.

I estimate these record cutters became obsolete when magnetic tape recorders became popular in the 1950s. The only real advantage to restoring a unit this old is for the experience and the satisfaction of bringing a very old piece of entertainment gear back to life...well, almost. As I said, blank recording discs haven't been available since shortly after tape recorders became popular, so even if you did get the record cutter in your WG combo to work, you would have no way to test it except, of course, to see that the recording stylus moves with any kind of audio input from the radio or a microphone. If the radio works, you can restore that, but again, don't expect miracles with any restoration efforts involving the record cutter. As I mentioned, these are almost hopelessly obsolete and are of little use except as curiosities or as museum pieces.
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Old 08-21-2018, 02:53 PM
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The primary of the transformer is definitely open verified by resistance test, and lack of plate voltage on the 6SN7 section driving it...

I understand the heads are crystal and probably bad, but if I rebuild or send out the head for a rebuild (west tech claims to rebuild these) it will not do me much good if the drive circuits are not operational.


Jeffhs the value of the cutting function to me has nothing to do with the day to day practicality of recording to 78RPM record in 2018...If it did I'd have dumped this machine MANY years ago. I don't talk about this much but I've long had an obsession with obsolete recording formats...I have and use tape formats you've probably never heard of going back to wire recorders... I've kept it and want it working primarily as an example of the technology. Also your understanding of the operational practicality of such a unit is poor...My unit came with many unused recording blanks and cutting styli (and I find additional recording blanks periodically), also I've seen people on youtube use units like mine to record on to laser rotted laser discs (and I'm sure it is not hard to get or create plastic discs that this thing can record on). Also as a big band and 78RPM aficionado there are some great performances that were recorded well after the end of 78s that I would love to dub to the format and add to a stack on one of my lighter tracking 40's record changers (or jukeboxes once I have funds to pursue that interest).
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Old 08-21-2018, 08:52 PM
EdKozk2 EdKozk2 is offline
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Hi Tom,
There was a magnetic cutting head produced that could be substituted for your crystal one. The the current 7000 ohm primary/ 70,000 ohm secondary impedance transformer can be switched to a standard 7000 ohm / 4 ohm transformer. The magnetic cutting head was Astatic M-41-3. The replacement transformer for the change over was Stancor A-3854 or A-3859.
My wife and picked up one of these Recordio's in January. I just recapped mine last month. I had to change the phono cartridge. The crystal cutter and transformer were both shot. The secondary of the transformer was open. I installed a standard speaker transformer for a 6V6 load (5000 ohm) to 4 ohm speaker. My Recordio uses the 6SN7 to drive the cutter. I ended up building a DIY magnetic cutter. It works well enough to at least record on plastic disks. The frequency response is limited, very weak on the high frequency end.
Ed
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Old 08-22-2018, 01:51 AM
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Quote:
Originally Posted by EdKozk2 View Post
Hi Tom,
There was a magnetic cutting head produced that could be substituted for your crystal one. The the current 7000 ohm primary/ 70,000 ohm secondary impedance transformer can be switched to a standard 7000 ohm / 4 ohm transformer. The magnetic cutting head was Astatic M-41-3. The replacement transformer for the change over was Stancor A-3854 or A-3859.
My wife and picked up one of these Recordio's in January. I just recapped mine last month. I had to change the phono cartridge. The crystal cutter and transformer were both shot. The secondary of the transformer was open. I installed a standard speaker transformer for a 6V6 load (5000 ohm) to 4 ohm speaker. My Recordio uses the 6SN7 to drive the cutter. I ended up building a DIY magnetic cutter. It works well enough to at least record on plastic disks. The frequency response is limited, very weak on the high frequency end.
Ed
Thanks for that excellent information Ed.
Today I spent some time taking stock of the record cutters I have and remembered I have more hiding. The Recordio's head is still unknown condition but I'm fairly confident it is equipped with a crystal cart. I had a spare cutter cart (that I pulled from a spare mech that I sold) that is the same size/shape...I opened the spare up to discover rotted crystal. I'm going to have figure out some form of signal source to test the Recordio's cart.

My memory of the Recordio working may have been wrong...At the time of that memory I owned a second no-name record player/cutter/amp that I still have that unit has a magnetic cutter cart that has continuity...That may have been what I was remembering. Neither unit is in great cosmetic condition...The No-name had much of the tweed eaten off its case when stored in the garage in Florida (damn cockroaches!) and the Recordio needs woodwork, grille cloth, and correct knobs, but has the factory stand (that makes it into a legged mini-console), and the original instruction book (and some accessories) going for it. Not sure if I'll fix one or both right now.

I have been toying with the idea of growing new Rochelle Salt crystal piezo elements to try in pick up carts. Lots of videos on making the crystals on youtube, but none trying to use them for the application or make them the right size... If I can make such a thing work for a pick up then maybe I could scale it up to a cutter cart. Supposedly the originals were all Rochelle Salt carts back then. I figure new Rochelle Salt elements must be the way that the places that rebuild 40's playback and cutter carts do it so if I can figure out the process I could do my own professional rebuilds. I may shelve the Recordio, for now, all is recapped and working but the cutter mode and I have other cutters.

Just a moment ago I remembered there is a cutter on my Philco BOL console too...Can't test it now but the head feels like the magnetic one in my no-name unit...Fingers crossed on that.
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