When I bought this
1976 vintage Snoopy telephone on eBay, the seller didn't disclose that the Volume level in the earpiece
was very low, including the ringtone. Technically it worked so I couldn't claim fraud, but it worked
poorly. So, I began doing a bit of research on the Internet and found that a lot of people were having
similar problems with the Snoopy phone and a couple other novelty models (Mickey Mouse, Winnie the Pooh,
M&Ms dude, et al) that were based off the same Western Electric design. I planned to clean up the
phone and put it into service, but wanted to make sure it was functioning properly before going to the
trouble. (see my other Peanuts paraphernalia)
The first thing I did was some standard continuity tests to make sure signals could flow from point
to point. I discovered a strange little plastic box that had a couple passive components and a single
IC package in it. Figuring it might be a diode bridge, I tested it and discovered that one of the four
diodes was open circuited and another other had a strange high resistance. I looked for a description
of the circuit on the Internet but did not find an exact reference to that box, just a polarity correction
circuit for instances where the house phone wiring was backwards (tip and ring reversed). That made
perfect sense for a bridge circuit. Rather than replacing the diodes, I used a plug-in telephone tester
to verify that my wall jack had the proper polarity and simply hardwired the phone's red and green input
wires to the network network terminal block. Doing so brought the ring tone Volume level back on par
with the voice Volume, but both were still too low.
After a little more
troubleshooting I discovered that one of the contact points in the keypad assembly was making intermittent
contact and always had high resistance (~200 ohms). Burnishing both the post and the metal leaf spring
brought it down to near zero ohms, so I did the same thing to the other switch points as well. I plugged
the phone back into the wall and viola!, a perfectly normally operating telephone!
Encouraged by my success, I bought a second Snoopy phone on eBay for parts to assemble the best I
could get from the two separate phones (the first had nicks on the handset). Now I have two Snoopy phones
that are functional. One is in very excellent condition cosmetically (for a 40-year-old phone) and the
other is nearly as good with only a couple minor marks.
During
the process I took a lot of photos. It is amazing how robust the components were back in the days when
only licensed manufacturers were permitted to build equipment for connecting to the public phone lines.
Bell Telephone Company was a true all-powerful monopoly before they were broken up in 1984 into 'Baby
Bells'. Soon thereafter a plethora of new phone models were available with increasingly feature-filled
capabilities. Before the breakup, Ma Bell would charge you for each telephone you had in your house.
I remember sometime in the early 1970s when my parents had to disconnect my sister's contraband Princess
phone because a man on our street that worked for the phone company warned us that Bell was performing
impedance tests in the area to determine whether people had more phones than they were being billed
for.
These photos were taken primarily to serve as documentation of how everything was configured prior
to a total disassembly and cleaning. I wanted to be sure to be able to put it back together later. I
do the same thing for a lot of repair projects instead of relying on an increasingly failing memory.
A couple years ago I needed to disassemble the timing assembly on my son's Ford Ranger truck and took
photos of the inside of it while removing the broken cam. It was nice to be able to refer back to the
images during reassembly to be sure it was going back together correctly. The entire thing was a pain
to get to behind the engine, and I didn't want to have to do it more than once. I'll eventually post
the cleaned-up and reassembled photos.
Component Overview (ringer side)
Case Top (topside)
Case Bottom (underside)
Polarity Corrector (case)
Ringer Assembly (bell)
Ringer Assembly
Network Block (plastic cover)
Network Block
Handset Switch (bottom)
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Component Overview (keypad side)
Case Top (underside)
Case Bottom (topside)
Polarity Corrector (bottom)
Ringer Assembly (close-up)
Ringer Assembly (bell off)
Network Block (top)
Network Block (bottom)
Handset Switch (top)
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Keypad Assembly (top edge)
Keypad Assembly (right edge)
Keypad Assembly (bottom edge)
Keypad Assembly (left edge)
Polarity Corrector (top)
Network Block (wiring overview)
Network Block (wiring right)
Network Block (wiring top)
Network Block (wiring left)
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Posted February 11, 2014
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