Michael,
Well - he said (in a subsequent post) that it had a transformer and
electrolytic. I surmise from that he has DC running around somewhere since
it apparently generates a signal. All one would need to do is trace the
voltage from the secondary to the elusive rectifier. Or one should find DC
across the electrolytic and be able to trace back towards the transformer
from there.
I'm sure he'll figure it out. If he has DC - he has a rectifier hidden
someplace. If he doesn't - it can't work (as he says).
Roger, KL7Q

Michael Black wrote in message
...

"Roger and Ute Brown" ) writes:

Check the tube base wiring against the 6L6 and
see if everything
goes to the correct pins for such a tube. It's possible you should have
a
tube which sports a rectifier (diode section) and another tube in the
same
envelope). At any rate - a part by part inspection resulting in a
schematic
will tell all!

I thought of that myself. While this transmitter is so simple it has
to be pretty generic, so there doesn't have to be an article about it, I
have seen "single tube" transmitters described in old magazines that
used something intended for AC/DC use, ie a power stage with a built in
rectifier that used a high filament voltage. I'm thinking 50L6, but I'm
not sure if that is right. I don't remember if there was something in an
octal package that ran off 117volts directly.

I don't think the original poster mentioned if there was a transformer,
and
somehow I suspect the lack of one would be a greater indicator of this
route.

Of course, selenium recitifiers may have had a brief enough life that
someone might not recognize one by sight.

Michael VE2BVW

The transmitter can work without a separate rectifier. I recall a circuit
from the 30's in which the transmitter tube is used also as the rectifier.
I think it was in the RCA handbook. I sort of recall an 813 tube, but that
may have been a bit early for the 813. Even in those days, it was not
"state of the art".

Now, I will have to look for the circuit, but the oscillator tube can also
serve as the rectifier. It complicates things a bit and is not in any of
the Handbooks. Never have seen a 6L6 circuit configured that way, but it
can be done and was done in the 30's in at least one circuit.

Colin K7FM




---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.783 / Virus Database: 529 - Release Date: 10/25/04

I am looking at "Practical Radio Telegraphy" dated 1928. The RCA P-8
transmitter is described with tube converter ET-3628.

This converter is a tube replacement for the "quenched and synchrnous gaps
formerly located on the power panel". it runs 1.5 kw using 2 tubes. One of
the problems mentioned is "fading or swinging signals", in which it is
stated that "such difficulties may be encountered in the case of a heavy sea
causing variation of the antenna capacity by the rolling of the vessel ..."
it is mentioned that if, on occasion, one tube burns out and there is no
replacement, the circuit may be operated as a half wave rectifier with just
one tube. Even more interesting is what to do if both tubes fail and no
spares are available: "the operator may connect his transmitter in
plain-aerial style. This is accomplished by removing all of the connections
from the three secondary terminals of the plate transformer and connecting
the antenna to one outside terminal of this transformer, and the ground to
the other. The safety gap shunted across the secondary terminals will then
function as an oscillatory spark discharger."

DO NOT TRY THIS AT HOME. I PRESUME MORE THAN ONE SAILOR TRIED CLEANING BIRD
POOP OFF THE TRANSMITTING AERIAL AND BECAME WELDED TO THE DECK WITH THIS
SYSTEM.

Using a Poulsen Tikker form of detection, this transmitter may not have
sounded that much different from those that had dc on the plates.

Colin K7FM


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.783 / Virus Database: 529 - Release Date: 10/25/04

Colin,
That's really interesting. I was not aware that could be done. However, I
would
think that the chances that the 6L6 circuit was configured to work in that
fashion
are slim at best (but then one never knows).
Thanks for the interesting information.
Roger, KL7Q

COLIN LAMB wrote in message
ink.net...
I am looking at "Practical Radio Telegraphy" dated 1928. The RCA P-8
transmitter is described with tube converter ET-3628.

This converter is a tube replacement for the "quenched and synchrnous gaps
formerly located on the power panel". it runs 1.5 kw using 2 tubes. One
of
the problems mentioned is "fading or swinging signals", in which it is
stated that "such difficulties may be encountered in the case of a heavy
sea
causing variation of the antenna capacity by the rolling of the vessel
...."
it is mentioned that if, on occasion, one tube burns out and there is no
replacement, the circuit may be operated as a half wave rectifier with
just
one tube. Even more interesting is what to do if both tubes fail and no
spares are available: "the operator may connect his transmitter in
plain-aerial style. This is accomplished by removing all of the
connections
from the three secondary terminals of the plate transformer and connecting
the antenna to one outside terminal of this transformer, and the ground to
the other. The safety gap shunted across the secondary terminals will
then
function as an oscillatory spark discharger."

DO NOT TRY THIS AT HOME. I PRESUME MORE THAN ONE SAILOR TRIED CLEANING
BIRD
POOP OFF THE TRANSMITTING AERIAL AND BECAME WELDED TO THE DECK WITH THIS
SYSTEM.

Using a Poulsen Tikker form of detection, this transmitter may not have
sounded that much different from those that had dc on the plates.

Colin K7FM


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.783 / Virus Database: 529 - Release Date: 10/25/04

Deep down in my memory banks, I recall seeing an OSS transmitter from WWII
that used a similar circuit to avoid the failure of a rectifier tube, where
the 6L6 was used as a rectifier also. It did make sense, since the
rectifier tube was more fragile than the metal 6L6. Otherwise, it would
make no sense, other than to confuse your buddy - like using a 6L6 for a
rectifier and a 5U4 for the final output stage (sure it can be done).

Colin K7FM


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.783 / Virus Database: 529 - Release Date: 10/25/04

Deep down in my memory banks, I recall seeing an OSS transmitter from WWII
that used a similar circuit to avoid the failure of a rectifier tube, where
the 6L6 was used as a rectifier also. It did make sense, since the
rectifier tube was more fragile than the metal 6L6. Otherwise, it would
make no sense, other than to confuse your buddy - like using a 6L6 for a
rectifier and a 5U4 for the final output stage (sure it can be done).

Colin K7FM


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.783 / Virus Database: 529 - Release Date: 10/25/04

Colin,
That's really interesting. I was not aware that could be done. However, I
would
think that the chances that the 6L6 circuit was configured to work in that
fashion
are slim at best (but then one never knows).
Thanks for the interesting information.
Roger, KL7Q

COLIN LAMB wrote in message
ink.net...
I am looking at "Practical Radio Telegraphy" dated 1928. The RCA P-8
transmitter is described with tube converter ET-3628.

This converter is a tube replacement for the "quenched and synchrnous gaps
formerly located on the power panel". it runs 1.5 kw using 2 tubes. One
of
the problems mentioned is "fading or swinging signals", in which it is
stated that "such difficulties may be encountered in the case of a heavy
sea
causing variation of the antenna capacity by the rolling of the vessel
...."
it is mentioned that if, on occasion, one tube burns out and there is no
replacement, the circuit may be operated as a half wave rectifier with
just
one tube. Even more interesting is what to do if both tubes fail and no
spares are available: "the operator may connect his transmitter in
plain-aerial style. This is accomplished by removing all of the
connections
from the three secondary terminals of the plate transformer and connecting
the antenna to one outside terminal of this transformer, and the ground to
the other. The safety gap shunted across the secondary terminals will
then
function as an oscillatory spark discharger."

DO NOT TRY THIS AT HOME. I PRESUME MORE THAN ONE SAILOR TRIED CLEANING
BIRD
POOP OFF THE TRANSMITTING AERIAL AND BECAME WELDED TO THE DECK WITH THIS
SYSTEM.

Using a Poulsen Tikker form of detection, this transmitter may not have
sounded that much different from those that had dc on the plates.

Colin K7FM


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.783 / Virus Database: 529 - Release Date: 10/25/04

I am looking at "Practical Radio Telegraphy" dated 1928. The RCA P-8
transmitter is described with tube converter ET-3628.

This converter is a tube replacement for the "quenched and synchrnous gaps
formerly located on the power panel". it runs 1.5 kw using 2 tubes. One of
the problems mentioned is "fading or swinging signals", in which it is
stated that "such difficulties may be encountered in the case of a heavy sea
causing variation of the antenna capacity by the rolling of the vessel ..."
it is mentioned that if, on occasion, one tube burns out and there is no
replacement, the circuit may be operated as a half wave rectifier with just
one tube. Even more interesting is what to do if both tubes fail and no
spares are available: "the operator may connect his transmitter in
plain-aerial style. This is accomplished by removing all of the connections
from the three secondary terminals of the plate transformer and connecting
the antenna to one outside terminal of this transformer, and the ground to
the other. The safety gap shunted across the secondary terminals will then
function as an oscillatory spark discharger."

DO NOT TRY THIS AT HOME. I PRESUME MORE THAN ONE SAILOR TRIED CLEANING BIRD
POOP OFF THE TRANSMITTING AERIAL AND BECAME WELDED TO THE DECK WITH THIS
SYSTEM.

Using a Poulsen Tikker form of detection, this transmitter may not have
sounded that much different from those that had dc on the plates.

Colin K7FM


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.783 / Virus Database: 529 - Release Date: 10/25/04

The transmitter can work without a separate rectifier. I recall a circuit
from the 30's in which the transmitter tube is used also as the rectifier.
I think it was in the RCA handbook. I sort of recall an 813 tube, but that
may have been a bit early for the 813. Even in those days, it was not
"state of the art".

Now, I will have to look for the circuit, but the oscillator tube can also
serve as the rectifier. It complicates things a bit and is not in any of
the Handbooks. Never have seen a 6L6 circuit configured that way, but it
can be done and was done in the 30's in at least one circuit.

Colin K7FM




---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.783 / Virus Database: 529 - Release Date: 10/25/04