Author Topic: Another orphan followed me home  (Read 3317 times)

TC Chris

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Re: Another orphan followed me home
« Reply #15 on: May 16, 2019, 11:51:57 PM »
Probably because the eye tubes are only in 6 volt, and their current rating probably didn't match the series-string tube currents.  Same for the IF, I bet.  But it does seem a strange way to cobble together a device.

Chris Campbell

Bill

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Re: Another orphan followed me home
« Reply #16 on: May 17, 2019, 10:58:10 AM »
Are we referring to the RCA 3 channel, or the Motorola 3 channel?   ::) ::) ;) ;) :)

Bill

electra225

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Re: Another orphan followed me home
« Reply #17 on: May 17, 2019, 11:11:05 PM »
The RCA.   ;)

The IF tube is a 6BA6, so wouldn't that run on a heater string?  The 6E5 eye tube I can understand.  I thought it was a rather interesting setup.  I had never seen a 35W4 on a power transformer before.  I reckon the 1:1 tap on the power transformer would serve as an ad hoc isolation transformer wouldn't it?  Probably has more to do with hum than isolation.
I don't need Google.  My wife says she knows everything.

TC Chris

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Re: Another orphan followed me home
« Reply #18 on: May 18, 2019, 06:15:29 PM »
I'm where the little "Home-Mark" is stashed, and after some more sump-pump follies and cutting  big yard of grass I decided to pull the back and measure the speakers from behind.  They qualify as 6" and 4".  The larger ones have these numbers:  9656 and 270411.  I assume the latter is the EIA code.  If anybody has their codes at hand, translate for me, please.  The smaller one is coded "Japan."  The V-M changer has a model no B1265--a simple 1200-series device. 

Maybe somebody will recognize the cartridge. 

Whoever made it, the model no. is intact on the torn label--336X.  And while it's not high-end and the height of its Fi is not very, it does have nice real veneers and ITT and Madison-Fielding label tubes (Mullards on the MPX device).  The Zenith hang-tag for a modular unit that came with it touts imitation wood-grain finish.  For me, the real thing is way better.

Chris Campbell

electra225

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Re: Another orphan followed me home
« Reply #19 on: May 18, 2019, 10:50:30 PM »
The "270411" is the speaker code.  "270" is for Quam-Nichols and the "411" is the 41st week of 1961.  That cartridge is quite similar to the one in one of the little GE stereos I have.  I'm guessing a Tetrad model.  ITT tubes were lower-end replacement brand.  I'll bet that little stereo sounds better than you think with a good set of speakers and some TLC.  It is definitely not a cheap piece of junk.  Quam was a good brand of speaker.  Mullard tubes are good.  VM changers are workhorses.  Simple might be a good description.  Nothing wrong with simple.   :) :)

I'd clean the cabinet up a bit, put some burlap speaker cloth in it.  That thing is cute as a bug.  I'd put that between a couple of big Magnavoxes and it would hold its head high.   :) :)

If you ever decide to kick that little stereo to the curb, please remember that I have a DANDY curb in front of my house!   :) :)
I don't need Google.  My wife says she knows everything.

electra225

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Re: Another orphan followed me home
« Reply #20 on: May 19, 2019, 09:50:56 AM »
The cartridge in my little GE stereo is a Ronette 106.  Looks very similar to yours.  I should learn not to post after work when I'm tired.  My brain works less than usual.   :-[ :-\ ;) :)
I don't need Google.  My wife says she knows everything.

TC Chris

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Re: Another orphan followed me home
« Reply #21 on: May 19, 2019, 10:47:09 AM »
I'm lucky that I have a replacement needle box that was in the console. It's a RonetteSA-5304-ST that replaces a whole bunch of other styli.  It's "for stereo cartridges of various makes, Astatic, BSR and Vaco (see Ronette's detailed cross reference chart)."  Yesterday I removed and straightened the stylus assembly.  It's screw-mounted and shaped just like the one on my childhood steel-cased RCA portable.

There's a bit of original grille cloth surviving on the inside.  It's one of those coarse weaves with a fine black cloth behind.  It's not clear if I could remove the speaker baffle boards for replacement--looks like "no"--so my plan is to cut tempered Masonite to fit the space, cut speaker holes, and cover that with the grille cloth.  Then that could just be pressed onto the front and secured.

It is a handsome little device.  Yesterday I fired it up, thinking I could get some sound out to the voice coil/dustcap remains of the speakers, but the wires from frame to voice coil had been broken on each one. Somebody has added--very carefully and well, looking almost original, wires from the speaker terminals to an RCA jack pair on the back.  If I make up some RCA plug speaker wires I can use remote speakers to test.  But those are at home where the device is not, so it requires planning.  Maybe next weekend.  Meanwhile, the FM stereo light did come on, so there's hope and B+, apparently.

Chris Campbell

electra225

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Re: Another orphan followed me home
« Reply #22 on: May 19, 2019, 04:54:22 PM »
Look to see how the Masonite speaker panels are secured to the cabinet.  I'm betting with staples.  If so, a rubber mallet, judiciously applied, may be enough to shake the panels loose without damage.  If they are glued, extra caution must be used so as not to bust the wood.  Fine paneling nails can be used to secure after repairs.  I like using black backing cloth under burlap if you decide to use that.  It is cheap and very forgiving to use.

You don't know at this point whether the cartridge is good or not, right?  You say you need six inch and four inch speakers?  What ohm rating?
I don't need Google.  My wife says she knows everything.

TC Chris

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Re: Another orphan followed me home
« Reply #23 on: May 19, 2019, 05:15:51 PM »
The 4" Japanese ones say 3.2 ohms, a standard rating for small speakers, I think.  I'll bring along a couple little Radio Shack models next weekend and try them.  They have screw terminals AND RCA jacks on the back so I could use regular RCA cables.  That cartridge is an unknown--it's easy for them to get banged up when people aren't using care.  The bent stylus was a bad sign.  We'll see.  The stereo light coming on is a good sign for FM.

FM stereo doesn't switch automatically, I suspect, and that's consistent with early practice.  If my speakers codes say 1961, that's the year FM stereo was approved, so it all fits.  The manufacturer may have had a good inventory of speakers, so it's clear that my device was from 1961 or shortly after.

My plan for the speaker grilles was to use a second tempered Masonite overlay to hold the cloth, unless it's really easy to get the original board off.  It's one piece, and the middle veneer section is fixed to it.

Meanwhile, I spent a rainy Sunday reorganizing my mother's garage so now the two cars--her old Subaru and the '61 Chevy--are side-by-side, instead of having the Chevy behind the Subaru (the garage is L-shaped).  Recycled half a lifetime's worth of cardboard....  The little console now has room to work on it.

Chris Campbell

electra225

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Re: Another orphan followed me home
« Reply #24 on: May 19, 2019, 05:36:55 PM »
It sound like getting the speaker boards out my not be practical.  What if you glued grille cloth on, then trimmed it with small lath of some kind?  That might be easier than fabricating entire speaker boards.  What I like about burlap is that it is easy to work with, yet you don't have to worry about pattern being straight.  If you get it close to straight, that is good enough.  Use Elmer's white glue that dries clear and dull.  You can iron out the fabric with a utility roller that is used for wallpaper and that.
I don't need Google.  My wife says she knows everything.

TC Chris

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Re: Another orphan followed me home
« Reply #25 on: May 19, 2019, 06:02:26 PM »
My first home-built speaker enclosures used burlap for the grille cloth.  They were small, back-vented reflex devices from plans in Hi-Fi/Stereo Review magazine.  Built one when I had a mono amp and another when I built my Heathkit AA-22 stereo amp.  Covered them in black Naugahyde. I used two GE 8" speakers that I had. Mr. Phillips, the neighbor with a table saw, must have cut the plywood for me. Still have 'em, of course.

Chris Campbell

electra225

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Re: Another orphan followed me home
« Reply #26 on: May 19, 2019, 08:03:42 PM »
Burlap gives speaker enclosures a clean, elegant look.  Much of the grille cloth on old radios is too busy to blend with modern furnishings.  My wife is very critical of most grille cloth used in old radios, even Magnavox.  I used black burlap in my little 616 and have had lots of positive comments.  I'm not going to try that with the ST, because I have already done it once.  I got the black burlap and the backing at Hobby Lobby.  You need to use backing on "yard goods" burlap, since it is prone to wrinkle and has little integrity.  The backing keeps it straight and keeps it from wrinkling.  My wife likes to move furniture around to create a different look.  The little stereo with black burlap goes with anything.
I don't need Google.  My wife says she knows everything.

TC Chris

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Re: Another orphan followed me home
« Reply #27 on: May 19, 2019, 10:56:40 PM »
Is "backing" some sort of iron-on fabric to add strength & substance?

Chris Campbell

electra225

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Re: Another orphan followed me home
« Reply #28 on: May 21, 2019, 08:17:11 AM »
The fabric backing I use with burlap is sold for that purpose.  It provides strength to the burlap so it does not move when the speaker cone moves air and it provides body to the burlap.  Burlap is pretty flimsy material by itself.  I glue the backing to the speaker board, then staple the burlap to the board from the back.  You can get backing in several colors.  The folks at Hobby Lobby or a fabric shop can advise you should you have other questions.  The backing is acoustically transparent, if that is a concern.
I don't need Google.  My wife says she knows everything.

electra225

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I don't need Google.  My wife says she knows everything.