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 IO91UX
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 IO91UX
2012/12/19 Graham < [email protected]>: >
Why the stabilised screen supply ? >
G.. It's embarassing. I like the glow of VR tubes! :-) 73,
Dimitris
VK1SV
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