Sound on Wire

The restoration of a Sears Silvertone Model 101.773 Wire Recorder
(Click on Images to see full size.)

It was the fall of 2010 when I stumbled across a late 1940s Sears Silvertone self-contained wire recorder at a flea market. The guy didnít know what it was, so after some haggling, he let me have it for nothing. It was the end of the day and he didnít want to hull it back to his place.

When I got it home, I opened it up to fine that someone had attempted to perform surgery on it. Parts floated around everywhere inside. Oh well, the Y2K thing. A go-around with the capacitor checker confirmed my suspicions. After recapping the whole thing, It played rather well except for the bad rubber rollers. So, to save them, I shaved off the unevenness on a lathe. Itís still a little rough but, it plays at the correct speed. This is because the metal take-up reel and motor capstan are still matched. Its sound is surprisingly clear. But again, I put it on a scope and found that 5 to maybe 6 kHz was its upper limit.


I looked around on the web but I couldnít figure out exactly what model it was. All the ones Iíve seen were meant to be used in a console such as the Silvertone 8125 (101.831-1 Type 47) console radio, record changer, and wire recorder, each device being separate. From time to time, recorders which were once in these consoles, turn up on eBay. The one I have was designed to be completely self-contained with an integrated amplifier and speaker mounted in the back. I even have the schematic. So, I presume it is a 101.773.

The recorder I have here may have a different main chassis in it. It appears that someone tore off the old tube layout label on the bottom cover and glued on another one.   The chassis is marked 101.773 and the layout and the diagram is for a 101.773-1 or revision 1. Two of the tubes are different.

Not having the correct schematic made it difficult to forensically reassemble the main chassis from the deconstruction some prior owner did to it, but it now works fine.

The tiny two-tube amp is a separate chassis and is mounted inside onto the left side of the case.

Well, this Silvertone is in bad cosmetic shape. Over the years it has gotten dinged up. I even had to pound out various dents in the gold painted aluminum shroud. It looksÖOK. Everything is there including the slightly bent-up escutcheon ring around the 6E5 recording level eye tube. However, the paint has been chipped off on its various outer parts. Someday I will work on restoring it, that is if I ever get over my disdain for Sears products.

Believe it or not, the legacy of stupid Sears engineering goes back to this machine. For example, the rubber rollers are never disengaged. As a result, dimples form where the idle rubber wheel is pressed against a metal roller for long periods of time. So, after I turn it off, I have to park the function lever in the rewind position so the playback doesnít get affected. There are a number of other issues such as the hard to find metal base style small-pin tubes indigenous to this period of Sears products and, not to mention, the record-play switch linkage.

Final note about this style of recorder: The take-up reel often doubled as a turntable. it spins at 78 RPMs. With the exception of Webster Chicago  most of the other wire recorders made in America that used the common WC spools have a tone arm. This Silvertone model 101.773 usually accompanied a radio and record changer, so, no tone arm.

This model I have seems to have been a last minute production. The instructions that came with the unit have an addendum page and schematic showing the revised addition of the audio amp and speaker.

Telechron Clock Timer -  Time-shifting

This may very well be the first consumer grade recording device designed to time-shift broadcasts. 

For quite some time I've looked around on the web and into other sources and I cannot find any consumer based equipment prior to this type of recording device that was equipped with a timer.  This model of wire recorder in a Silvertone 8125 console could easily be used to record programs from the radio at a set time very much the same way as a modern-day VCR or DVR.

The problem was that in 1947 when these were being manufactured, television was coming into its own .  Also, the cost of this system was rather pricy and only about 500 of these consoles were ever sold.