> The easiest way to use an oscilloscope as a waveform monitor is to obtain
> and use a Heathkit SB-610 waveform monitor.
*** I have one of these. Works OK. It died a few months ago - was the
rectifier and capacitor for the -1700V supply. My SB610 does not have a
sharp trace - it's sharp in the middle, and widens toward the edges.
Apparently this is because the SB610 does not have an astigmatism control.
This would be a variable voltage applied to one of the grids.
I have seen some mention of people adding such to the 610 but have
not found a schematic anywhere. If I did find one, I'd be tempted to do
it - but the flaring trace is not quite annoying enough to go
experimenting.
The 610 is not well sealed for RF. It's probably the leakiest thing
in the shack.
- Jerry Kaidor, KF6VB
>
> 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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>
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