Sound on Wire

The Restoration of a Webster Chicago 178-1 Wire Recorder.
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One day while looking on eBay, I happened upon an unusual wire recorder. It was a Webster Chicago Model 78. It struck a nerve and I then remembered a high school friend who's father had one in his ham shack. I then looked further and found several 40s and 50s articles about using these recorders for amateur radio work.

I tried to bid on it but it went for about $80.00, a little more than I wanted to pay for something that was banged up and needed restoration.

These recorders are what I consider to be OK.  They are small and they work as good as the rest.  So, if I were to add a recorder to my collection of vintage electronic stuff, the 78 or 178 would be one.

I was at a friend’s house drinking his beer when he asked me to help him in his dingy basement. While we were looking for something in the darkness, I noticed something wrapped in some kind of dusty vinyl crammed up in the rafters. The vinyl turned out to be an opaque 50s flowered shower curtain. What was wrapped inside was a small Webster Chicago Wire Recorder. My buddy didn’t know what it was, nor did he care.  He also pointed out a cardboard box full of wire spools.

After I got it all home, I completely unwrapped the recorder. Along with several dozen spools, I noticed that there was a mike and an additional cloth covered cord for hooking the recorder to an external amp. The recorder seemed to be hardly used. In fact, after I cleaned up each of its exterior parts and reassembled everything, it was like new.

Of course, I recapped the whole thing and replaced resisters that weren't within tolerance, that being most of them. I then cleaned up and oiled the various bearing surfaces.  The original line cord was still in really good condition.  Oh yes, the filter capacitor seemed new, like someone had already replaced it.  It tested out really good.  Then it was time for the initial power-on test. 

Well, I soon figured out why it was put up in the rafters in the first place. Its record/playback head coil was open, meaning; no resistance could be measured across the coil. Now there’s something I never saw on eBay, a Webster Chicago wire recorder head. So, let’s take it apart and…

The round head plugs in. It and its brown Bakelite cover are secured in place with a long thin bolt down through the top of the cover. The head itself is sandwiched between two small steel caps. These are also held together with another shorter thin bolt and a nut.

The magnetic conductive material is some kind of ferrite material. It is put together in a D shape with the center element inserted and soldered together on the front. This is sandwiched between two supporting U shaped steel pieces. The only thing I could do to access the coil was to snap it apart. It was a clean break at it. The back end was dovetailed, so it slipped out. I could then access the bad coil and remove the still sticky clear yellowed plastic tape. After exposing the coil of wire, I very fortunately found the end of the tiny strand. I unraveled one turn. I had to then gently scrape off the varnish on this tiny tenth of a human hair wire before soldering it back onto the much thicker lead wire. I wrapped it around the lead and soldered them together. I then retaped the two coils. I used super glue instead of solder to rejoin the two halves of the D element. After some shaky moments, the head was reassembled and the four leads soldered back into the plug pins.

 
Now the machine is back together and despite it being a simple design with only four tubes and a few components, it plays as well as other recorders.

This recorder is, in modern terms, a recording deck, meaning, it does not have an integrated audio amplifier and speaker. The unit requires an external amplifier…which I feel is OK.

The four pushbuttons on the front are rudimentary. Two are for record and only one is for play. The other, the far right button (4), does nothing. The left two record buttons are: far left, record from the front plug (mike), and the second, record from the playback line level output connector on the back. The third button is the playback button.  I suspect this switch was used in a variety of recorders and the fourth was for playing through the speaker amp built into the Model 18 dictating recorder. The later Model 228 only had two buttons.

This recorder came with a cable with a 4-pin female connector for recording and playback at line level. It has three wires or two pairs, one shielded for both record/playback, and the other two wires are for switching something on. When pushing in the play button, it closes a connection across the two wires.

The micro-amp (vu) meter only works on either record function.

Note. Unlike the Sears Silvertone wire recorders, there is no record safety interlock on any of the Webster Chicago machines.

I would display the Schematics except the one I have is still copywrited and is available on www.samswebsite.com. I do have the schematic for the 178

They only have SET 113, FOLDER 12 for Webster Chicago Model 178.
I have the Model 178-1 circa 1948. When I find an original manual and schematic, I will display them.