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Old 05-11-2016, 03:21 PM
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DavGoodlin DavGoodlin is offline
Motorola Minion
 
Join Date: Aug 2011
Location: near Strasburg PA
Posts: 3,400
When it comes to putting $$ in, look before you leap. I offer a different Sears as an example. Pardon the thread creep but I believe this is german to the discussion, IMHO.

First the console:
This Sears came from a yard sale last summer for $20. It was grimy but dry and complete with ALL the hang tags, service manual, parts list and schematic. Model 6066/528.63560, a 1965 Warwick-built SS chassis with Crescent changer/EV150 cartridge. It has a rear connection and slide switch for connecting 8-ohm remote speakers. The 10" speakers are 16 ohm with NP cap to 16 ohm 5" and 30 ohm 3" cone tweets. If you move the slider to use both internal and external speakers, a 22 ohm resistor is placed in series with the ext spkr screws AND an 8-ohm is then placed in series with the internal speakers.

The condition. I saw no evidence of any servicing after removing 20+ screws hold the back cover. I dutifully cleaned the selector and pots with DeOxit.

The receiver barely made sound and only when tuned to the usual strong stations, I figured the electrolytic coupling caps needed replacement so I got right to work and replaced the 4-3mf and two 150mf output coupling caps. Little improvement was noted and voltages on the drivers-outputs were consistent with the schematic. I got healthy hum when putting my fingers on the phono preamp input.
It sounded just like two bad speakers, so I pull one of the 10 inchers - the cone, compliance and voice coil was in great condition and not rubbing. It even passed Reece's patented thump test, when I smacked the magnet with my palm, it was met with a solid "thunk". OK....
Was the radio and discriminator/mpx demod section at fault? So I bridged new caps and checked voltages there - nothing improved

OK, now lets assume this unit has a receiver problem and serious bench time with signal generators are required Next!

What if we just do the record changer restoration and it comes alive??? OK but that is more work.
Then I looked at the cart and the stylus and pickup bridge was gone, yet it made noise when rubbing around where it would be. I just happened to have used cartridge and bracket that would work, an Astatic 710 (Euphonics style) with flat connectors just like the OEM E-V cart. I refused to rob any of my 3 or 4 Magnavox Micromatics that have a EV-150/158, those consoles might just be less of a PITA than this one has been.

The idler pulley is a small tire- big tire type, no flat spots or nicks. Cleaned up with rubber renu, and put back on. The platter started to spin but with lots of noise. Now what??? Looking very closely at the platter then the aluminum drive turret on the motor answered that one, the ":wedding cake" was worn down at each step such that the pulley could not make solid flat contact on both 45 and 33 rpm. More parts neededof course.. then I spun a good record anyway and it sounded just like the radio

OK, REALLY what can I expect from a worn out cart/stylus and anyway.
The last straw came when I connected a small portable CD player to the phono input and IT sounded as crappy as both the record and the radio.... back to square one. The amp IS the main problem after all this mucking about, let alone issues with the Crescent changer which are also present in a portable Sears I just bout a new Astatic 275d cart for.

If someone wants to refit this console with another record changer and receiver chassis, they can have at it for a song. It also has a factory schematic but the 5-year warranty on the transistors has passed and I suspect that IS the real problem. Anyway, where can you get good cheap germanium replacement transistors anyway?. The only thing this console is good for is the MCM walnut cabinet, still dirty - at least I'm smart enough after all these years to clean-refinish and detail ONLY if I can listen to it play nicely while doing so.

But I have too many more promising and frankly interesting units (think RCA-Magnavox-Motorola- Philco) to restore, plus paying jobs to occupy my limited time and finance the parts Ill need.
Besides, nobody is beating down my shop door to buy these old ceramic cart units anyway:boring
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-Dave G

Last edited by DavGoodlin; 05-11-2016 at 03:40 PM. Reason: add paragraph spaces
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