The easiest way to use an oscilloscope as a waveform monitor is to obtain
and use a Heathkit SB-610 waveform monitor.
SB-610 manuals have a decent tutorial on their use.
Another route would be to obtain an analog 100 MHz service oscilloscope,
such as a Tektronix 465, and connect the input of the 'scope to the center
conductor of your antenna feed line. Set the scope to trigger on AC, auto
trigger and a 2ms (millisecond) sweep rate. You will (should) see a trace.
Adjust the vertical gain as desired while transmitting a carrier into a
dummy load.
Then when you talk into your microphone your voice peaks should just
approach the 100% carrier level. If your voice peaks exceed that level your
amplifier will be flat topping and splattering across the band. If the
peaks are less than 100% you are not using your amplifier to full
capability.
When you get used to the AC and auto trigger you can experiment with
internal triggering to obtain a stable waveform on ssb and or cw.
One of my several pending projects is to modify an old 3" RCA oscilloscope
for waveform duty by installing a couple of SO-239 rf connectors, looping
the center conductors together, and running a lead from the center conductor
wire through a decoupling capacitor to one of the vertical deflection
plates.
If you can find an oscilloscope that does not have triggered sweep you can
obtain these really, really cheap and the CRT (cathode ray tube) will
probably have very little use as these 'scopes did not work very well and
had very little usefulness. First, make sure it works, then install a
couple of SO-239's for RF feedthrough, tap a bit of the RF through a
capacitor to one of the vertical deflection plates and you are in business
for signals below 30 MHz.
de Paul, W8AEF
-----Original Message-----
From: Jukka Tarvainen
Sent: Saturday, December 08, 2012 12:54 PM
To: amps@contesting.com
Subject: Re: [Amps] Vacuum Relay
I use an oscilloscope waveform monitor and it was very obvious on the
scope,
but for some reason not many hams use a scope as a waveform monitor.
Would be nice to have how to instructions for dummies on this subject.
73 de Jukka OH4MFA, OG4T
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