7 transistor CB Transceiver
 

Hi:
can anyone give me any info on this rig? My student gave me two of them ,
his granma passed away and had them around the house.
Here are the specs. Anyone know about
1)Generally when they were built
2)Are they worth anything, other than a few bucks that a handheld CB radio
with one channel would be

7-Transistor Citizen Band Transceiver
(210-0102) Specifications Faxback Doc. # 45541

Circuit:
Receiver Section: .......................... Superhetrodyne with crystal
controlled local oscillator
Transmitting Section: .................... Crystal controlled oscillator
Semi-Conductors: ................................ 7-transistor and 1-diode
Frequency: ........................................ 27.085 MC (Channel 11)
Frequency Tolerance: ................................... plus/minus 0.005%
Transmitting Power Input: ............................... 100 mW (Maximum)
Audio Output Power: ..................................... 130 mW (Maximum)
I. F. Frequency: .................................................. 455 kC
Speaker: ..................................... 2 1/4" dia. PM Dynamic Type
Antenna: ...................................... Single Element Rod Antenna
Dimension: .......................................... 6" x 2 5/8" x 1 1/4"
Battery: ............................................. 9V standard battery

Thanks!
Tom

In article ,
TC Dufresne wrote:
Hi:
can anyone give me any info on this rig? My student gave me two of them ,
his granma passed away and had them around the house.
Here are the specs. Anyone know about
1)Generally when they were built
2)Are they worth anything, other than a few bucks that a handheld CB radio
with one channel would be

7-Transistor Citizen Band Transceiver
(210-0102) Specifications Faxback Doc. # 45541

This is a Radio Shack part number.

Cheap walkie-talkies on the CB band were very popular until the late
eighties, I think, when the 49 MHz band opened up for this sort of
thing. Most of them are not very useful because they do not have a
squelch.

Circuit:
Receiver Section: .......................... Superhetrodyne with crystal
controlled local oscillator
Transmitting Section: .................... Crystal controlled oscillator
Semi-Conductors: ................................ 7-transistor and 1-diode
Frequency: ........................................ 27.085 MC (Channel 11)
Frequency Tolerance: ................................... plus/minus 0.005%
Transmitting Power Input: ............................... 100 mW (Maximum)
Audio Output Power: ..................................... 130 mW (Maximum)
I. F. Frequency: .................................................. 455 kC
Speaker: ..................................... 2 1/4" dia. PM Dynamic Type
Antenna: ...................................... Single Element Rod Antenna
Dimension: .......................................... 6" x 2 5/8" x 1 1/4"
Battery: ............................................. 9V standard battery

This appears to be better than most of them if only because it has
a superhet receive section. Where did you get these specs? Ask
Radio Shack for the schematics.

I doubt these are worth anything. When I was a kid people used to
move stuff like this to 10M AM, though. Invariably the modulation
levels were way low on the things.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Scott Dorsey ) writes:

I doubt these are worth anything. When I was a kid people used to
move stuff like this to 10M AM, though. Invariably the modulation
levels were way low on the things.
--scott

But most of the time, the walkie talkies available to convert had
superregen receivers, and the transmitter was more or less making
the superregen stage a crystal controlled oscillator. The low modulation
came because one was using a speaker for the microphone, and there
was a mismatch along the way. Every so often, you'd see a bit of filler
in the magazines talking about this, and suggesting wiring in another
transformer.

This may not apply with one using a superhet receiver. I can't say
I've ever seen a schematic for the transmitter in one, but since they
have added enough to make a superhet receiver, they may not be skimping
as much and the modulation levels better.

Michael VE2BVW

Michael Black wrote:
Scott Dorsey ) writes:

I doubt these are worth anything. When I was a kid people used to
move stuff like this to 10M AM, though. Invariably the modulation
levels were way low on the things.

But most of the time, the walkie talkies available to convert had
superregen receivers, and the transmitter was more or less making
the superregen stage a crystal controlled oscillator. The low modulation
came because one was using a speaker for the microphone, and there
was a mismatch along the way. Every so often, you'd see a bit of filler
in the magazines talking about this, and suggesting wiring in another
transformer.

Right!

This may not apply with one using a superhet receiver. I can't say
I've ever seen a schematic for the transmitter in one, but since they
have added enough to make a superhet receiver, they may not be skimping
as much and the modulation levels better.

Somewhere around here I have a Lafayette unit that has a superhet receiver
in it. I bought it at a hamfest in the seventies with the intention of
modifying it, found out that it was broken, and it's been sitting in the
inbox since then.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."