Can'not go too long without gasolina into the 3/4 wave FireStick in my car.
No. 220uf uf in parralel series. Too much soldering. Six yields aprox 144uf.
This is better. 3x1000uf ! In series 333uf.
When I shorted the new caps to chassis ground. Boom. As loud as a firecracker !
lot of reserve gasolina.
The electronic gremlins continued the havoc. 220uf 16v went bad in the
vintage Teaberry Stalker psu board. Huge AC Hum on the air ! 10 minutes fixed. Lo &
behold. Issue with the mic connector. On the modified Turner + 3. Late tired.
Just stuck on the stock mic.
Forgot. Will need part of the space that the soft start occupies for the input IMD filter.
Spice model done awhile back. Have the components. Just got to put in on a circuit board.
Possibly this module will handle 100 Watts +. Guess will find out.
Input IMD filter board is found on all modern Amateur linears. Associated with that is an
impedance matching L circuit. DIY or upgrade of an old all band ham box. It is sugested
strongly among this group. To install one. Possibly several. One for each amateur band.
Biggest complaint against Sweep tube foot warmers. Is the gremlin IMD Havoc they create
across the spectrum ! Some hams might be pleased ha ha !
Though not a ham. I decided to clean my amps up ! Possibly another kit also !
Length of coax can play a part. The filter board has to be as close as possible to the input of
the driver tubes "Cathode". That will be the next sub project.
Lo & behold. The G1 control grid bias is supplied from the High voltage ! Later grey 10 tubers
@ the beige brown D&A's. Negative grid voltage bias is coming off one of the fillament
windings ?
Perhaps when the resident ham technician engineer moved on. The new tech decided to
put his/her ideas unto the D&A line of amps ?
I will experiment later. But the DIY Audio Gurus. Some of them like this method of providing G1
grid bias. I feel it is superior to the later D&A amps. No need to waste precious time.
Installing my own.
If u want to learn about Sweep tubes. Study the material available online concerning Tube
audio amplifiers ! Small but active group of experimenters. 6L6 & all its derivatives. Kt88 etc.
6BG6. Which is a Sweep ! 807 transmitting tubes were used to power movie theatre P.A.
systems back in the day ! Even 813s. Fogetabout about most of the ham literature. Unless u
R
going to build some home brew Monster to put on 11 meters with 3000v to 5000v at the
plate.
The bowl certainly has several cbers running such equipment. One day maybe. Will purchase
a few broadcast/radio station type tubes. & build a Nuke linear.
For now it is sweeps. Enjoy the photos. One is new Full wave bridge mounted on screw type
wire strip.
Checked again all 8 finals. 3 borderline. Usable.
But I want maximum gasolina in the wire.
But of course. A price to pay in time. Output impedance has changed. The current tank coil is
now out of resonance. ehh Have a box full of tank coils I have made thru the years. About
one hour. Maybe 2 ? Found one I made for another amp a few yrs ago that was not the
correct inductance. For that box. 1/4 soft copper. Poor Q of 8.5. Wide barely fits in the box.
My experience. A larger diameter RF tank is best. Anyway. She said wider is better than longer.
Thats what she said !
8 watts in. 650 watts RMS out ! x 4 2600 watts AM PEP Next post will have pics.
On 27.185.
Eat ur hearts out QRP operators Ha Ha !
Tomorrow. Will role another RF tank coil out of nickel plated soft copper tubing. With the
same inductance. But a much higher Q. Q is very important. 10-15 Q. Around 11-12 is optimal for freeband & 11 meters. My experience.
A Q lower than 10. Results in smaller number of channels that
can be tuned at full output. Too high of a quality factor. Q. Results in loosing watts.
The RF tank Coil becomes a heating element !
Even the low setting on this 12 tuber. Somewhat came back to life with the tube swap. Don't
fully understand it yet.
This is a series circuit. A change in the driver circuit affects the finals circuit. A change in the
finals affects the drivers. Including a change in the transceiver"cb radio".
Yes
This is the way it is with 6LQ6's. Unless U have a stash. Of the D&A labelled 6MJ6, lq6's.
Iether it was RCA or GE that supplied D&A manufacturing.
These tubes had more uniform input "cathode" & output "Plate" impedances.
Decided to leave the Chrome case on the other 12 tuber I posess.
An early version with cloth covered leads on the Stancor trannys.
One of these days.
Will get the correct paint. Just refinish the case. One of these days !
Stay tuned. This aged Phantom. Will be promoted. To a Warrior soon !
73s