Sort of boat anchor
 

Hi gang,
I'm looking for the schematic of the old Archer "Space Patrol" walkie
talkie or similar. I think this tpye all used a very similar circuit with a
superregenerative rx that used the same stage as a non-crystal controlled
oscillator on tx along with a 2(?) stage audio amp.

Any help?

Tnx

Bob WB0POQ

Sort of boat anchor
 

Bob wrote:
I'm looking for the schematic of the old Archer "Space Patrol" walkie
talkie or similar. I think this tpye all used a very similar circuit with a
superregenerative rx that used the same stage as a non-crystal controlled
oscillator on tx along with a 2(?) stage audio amp.

A lot of companies in Japan made these things, and they all copied one
another in much the way Chinese manufacturers do today.

Here's a typical design:
http://yb3td.com/data/walkietalkie.html

As I recall, the Archers that I had as a kid were crystal-controlled for
transmit but used an adjustable LC network for receive tuning. I remember
moving one to 10M at one point but the audio quality was very bad and of
course there was no squelch...
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Sort of boat anchor
 

Hi Scott,
Thanks for the response. I found that site a few days ago, and was playing
around trying to get that circuit to work, until I noticed that there is no
DC path for collector current for Q1.
Also, there seems to be an issue with how L1 and L2 and the associated caps
are connected. I moved a few things around and got Q1 to work as an
oscillator and a superregen detector (I think), but have not built up the
audio and the switching circuits yet.
I'm still hoping to find some other examples of these cute little rigs. :)

Bob

"Scott Dorsey" wrote in message
...
Bob wrote:
I'm looking for the schematic of the old Archer "Space Patrol" walkie
talkie or similar. I think this tpye all used a very similar circuit with
a
superregenerative rx that used the same stage as a non-crystal controlled
oscillator on tx along with a 2(?) stage audio amp.

A lot of companies in Japan made these things, and they all copied one
another in much the way Chinese manufacturers do today.

Here's a typical design:
http://yb3td.com/data/walkietalkie.html

As I recall, the Archers that I had as a kid were crystal-controlled for
transmit but used an adjustable LC network for receive tuning. I remember
moving one to 10M at one point but the audio quality was very bad and of
course there was no squelch...
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Sort of boat anchor
 

In article , b wrote:
Thanks for the response. I found that site a few days ago, and was playing
around trying to get that circuit to work, until I noticed that there is no
DC path for collector current for Q1.

Hmm... you're right, that's really creepy. You think maybe base and collector
are swapped here?

I was thinking at first that maybe the base leakage did the trick, which
could be possible if it's a germanium type.

Also, there seems to be an issue with how L1 and L2 and the associated caps
are connected. I moved a few things around and got Q1 to work as an
oscillator and a superregen detector (I think), but have not built up the
audio and the switching circuits yet.
I'm still hoping to find some other examples of these cute little rigs. :)

I can send you a Lafayette one if I can find it. You're welcome to draw the
schematic out.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Sort of boat anchor
 

Scott,
I don't think the base and collector are swapped as the biasing looks
right as drawn on the presumed base, plus, if so then there would be no path
for base current. ;) ;)
Thanks for the offer of the Lafayette, I'd love to get a look at it.

Bob



"Scott Dorsey" wrote in message
...
In article , b wrote:
Thanks for the response. I found that site a few days ago, and was
playing
around trying to get that circuit to work, until I noticed that there is
no
DC path for collector current for Q1.

Hmm... you're right, that's really creepy. You think maybe base and
collector
are swapped here?

I was thinking at first that maybe the base leakage did the trick, which
could be possible if it's a germanium type.

Also, there seems to be an issue with how L1 and L2 and the associated
caps
are connected. I moved a few things around and got Q1 to work as an
oscillator and a superregen detector (I think), but have not built up the
audio and the switching circuits yet.
I'm still hoping to find some other examples of these cute little rigs.
:)

I can send you a Lafayette one if I can find it. You're welcome to draw
the
schematic out.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Sort of boat anchor
 

In article , b wrote:
Scott,
I don't think the base and collector are swapped as the biasing looks
right as drawn on the presumed base, plus, if so then there would be no path
for base current. ;) ;)
Thanks for the offer of the Lafayette, I'd love to get a look at it.

Give me an address and I will mail it. Your email in your post is not
valid.

Looking inside it, it looks way higher quality than the Archer. It has two
transformers inside!
--scott

I will say, though, that the RF performance on the Teenage Mutant Ninja
Turtle 49 Mhz walkie-talkie when moved to 6M is much better than on the
Archer Space Cadet walkie-talkie when moved to 10M. Either one is really
fun to write on a QSL card, though.

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Sort of boat anchor
 

On Thu, 10 Dec 2009, Scott Dorsey wrote:

In article , b wrote:
Thanks for the response. I found that site a few days ago, and was playing
around trying to get that circuit to work, until I noticed that there is no
DC path for collector current for Q1.

Hmm... you're right, that's really creepy. You think maybe base and collector
are swapped here?

I was thinking at first that maybe the base leakage did the trick, which
could be possible if it's a germanium type.

Also, there seems to be an issue with how L1 and L2 and the associated caps
are connected. I moved a few things around and got Q1 to work as an
oscillator and a superregen detector (I think), but have not built up the
audio and the switching circuits yet.
I'm still hoping to find some other examples of these cute little rigs. :)

I can send you a Lafayette one if I can find it. You're welcome to draw the
schematic out.

I think you're right, the circuits were so simple that there wasn't much
variation. Any schematic, I suspect they are in the RCA transistor guides
among other places) would make a good start for circuit tracing. You have
an end circuit to visualize and use the actual circuitry to "test" the
schematic, either it's going to match or be close.

Michael VE2BVW

Sort of boat anchor
 

In article , b wrote:
Scott,
I don't think the base and collector are swapped as the biasing looks
right as drawn on the presumed base, plus, if so then there would be no path
for base current. ;) ;)
Thanks for the offer of the Lafayette, I'd love to get a look at it.

No joke. Get me your physical mailing address and I'll send it to you.
But you have to email me your address.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Sort of boat anchor
 

* I'm looking for the schematic of the old Archer "Space Patrol" walkie
talkie or similar. *I think this tpye all used a very similar circuit with a
superregenerative rx that used the same stage as a non-crystal controlled
oscillator on tx along with a 2(?) stage audio amp.

I can email scanned pages of the entire "manual" (two pages!-) of the
Archer
60-4005 "Space Patrol Walkie Talkie" or I can put them on my website
and
let you snarf them yourself. Your call.
--W0PBV.