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Power corrupts ..!
Yes that is probably
quantising problems with the a/d conversations
, its quite a big step response
Still worth having a look with
the audio-spec analyser for supply components ,
with cheap (s/h) usb sound cards , its a cheap but
useful test instrument
Not sure how a L/C network would
handle fast keying ? was the tx a cw beacon
or modulated beacon ? I use
a hex-fet series stabilised for
my 12v 20 amp supply and one of
2 500 watt 24v and 1.5 Kw 50 v switch
mode supplies
Good luck ..
73 -G..
Sent: Tuesday, August 09, 2011 4:57 PM
Subject: Re: LF: 137 ck
Graham
The display looks clean this end also the audio sounds
pure with no 100 hz hum as monitored on an independent RX
I have the proper C's es L for decouping as per Decca
instructions with this TX.
With a strong signal on some Grabbers there will be
the dog bone effect with leading/trailing edge blips from keying carrier
on/off
but on scope no transients visible.
73 de mal/g3kev
----- Original Message -----
Sent: Monday, August 08, 2011 11:49
PM
Subject: Re: LF: 137 ck
That's the problem with
modern digital technology , the dynamic range
exceeds , that of the MK-1 eye ball , 30 db
is 1000:1 , will show at 20 db over the noise
and would not show on the scope
Use a reasonable
decoupling capacitor , and look at the psu
voltage using a (cheap) sound card
(with high z resistive ladder for safety) ..use
Wolf's SPEC-LAB to view the dB
attenuation at 50, 100, 150 , 200 Hz etc
Depending on the loop
bandwidth of the stabiliser , keying may also
induce transits , use the peak hold to observe
the generated spectrum
G..
Sent: Monday, August 08, 2011 8:29 PM
Subject: Re: LF: 137 ck
No hum Gary
I am monitoring on the scope and sig is vy
clean
mal/g3kev
----- Original Message -----
Sent: Monday, August 08, 2011 8:19
PM
Subject: Re: LF: 137 ck
OK Mal,
Captures are at 10 minute intervals, but I have saved you going to
SpecSavers as I have enlarged the frequency readout.
BTW...do you have some 100Hz hum on your transmission, look at my
grabber to check.
73
Gary - G4WGT.
On 8 August 2011 19:28, mal hamilton <[email protected]>
wrote:
Yes Gary
Your grabber seems to have a long delay before
display es the times and freq hard to read
otherwise sensitivity seems ok at present for
distance
73 de mal/g3kev
----- Original Message -----
Sent: Monday, August 08, 2011 7:21
PM
Subject: Re: LF: 137 ck
Mal,
You wrote.........While testing
earlier find NO UK GRABBERS working
My 500kHz & 137kHz grabber runs
24/7....
Gary - G4WGT.
On 8 August 2011 18:33, mal hamilton <[email protected]> wrote:
Just finished my new PSU 60V/10A psu. While
testing earlier find NO UK GRABBERS working and DK7FC has a SPURIOUS
wobble signal right on 137.7
I will be QRV for a while from now on 137.7 qrs3
for DX qso's and will work locals on CW
73 De Mal/G3KEV
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