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Now there is a idea , could use a
music synth to make a wobbly note , and send
it via the ssb exciter , for a real retro vintage
cw sound ?
just had a long retro data qso with
Chris xiz , on 502 , must be 2 years at least
since used rtty , beacon still running
now , not sure if anyone is still monitoring
, all this web linking has spoiled things
!
73 -G..
Sent: Wednesday, December 19, 2012 6:53 PM
Subject: Re: LF: Better picture of the 807 based 500kHz
TX
OK Graham
Good point!
But it doesn't jump it chirps quite pleasently Louis PA0LCE runs one on 500kc/s and tells me
ops like the Retro sound.
73 es GL Pete M0FMT IO91UX
Probably a early form of Spread
Spectrum , hard to JAM if is its
jumping about the band and difficult
to make a fake transmission if the Tx has a
wobbly bob signature : )
G..
Sent: Wednesday, December 19, 2012 5:42 PM
Subject: Re: LF: Better picture of the 807 based 500kHz
TX
OK Mal
Point taken. I was referring to a "Power"
oscillator like a single 6L6 used as an Xtal oscillator running at 15 / 20Watts
which means normally there is insufficient current (really)
from a VR tube
for the Anode(plate) so all that is necessary is to stab the screen. Otherwise
I totally agree.
I do know the standard T1154 chirps well. There is a PA0 who runs
one on 500 and I am sure you have worked him it is like a signature
signal HI.
I think there was some kind unpleasantness going on at the
time of the T1154 manufacture so the fine points of frequency
control was probably a low priority.
73 es GL
Pete M0FMT IO91 UX
Hi Pete
Stabilise both Plate es Screen on an Oscillator,
followed by a Cathode follower to avoid chirp and osc pulling.
The T1154 was very unstable with a bad chirp,
surprised it ever passed Quality Control
G3KEV
-----
Original Message -----
Sent:
Wednesday, December 19, 2012 10:08 AM
Subject:
Fw: LF:
Better picture of the 807 based 500kHz TX
Try again minus cct too big I think.
73 es GL Pete M0FMT IO91 UX
Hi Dimitris and group
I have not seen the schematic but it is usual to stabilise
the screen of a power oscillator to reduce chirp on key
down.
Now you have shown us yours I will show you mine. I usually
sketch the schamatic after the event so foregive the
presentation on the back of an envelope.
I now get at least 4Watts after adjusting the ant link
coupling away from the chasis. Best audible DX Kent 80miles
best Opera DX PA0 land.
73 es GL Pete M0FMT IO91 UX
2012/12/19 Graham
< [email protected]>: >
Why the stabilised screen supply ? >
G.. It's embarassing. I like the glow of VR tubes!
:-) 73, Dimitris VK1 SV
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