Making a simple 'scope !!!

[Inty]

I made a simple scope with this metod :
I got from the scrap an old b/w set/monitor and another small color set that
didn't work well but there is HV !
I cut the wires to the horizontal yoke, on the b/w set I got a line across
the screen, well ! I turned off it. Then I connected the two wires of the
yoke to a simple bf amplificator ad injected an audio signal into the
amplificator. Immediately I seen on the CRT a glowing line, well, it's the
signal !!! Then I rotate G2s pot to get a more brighter line (the set was
junk... and i don't mind how it can last !)...
For the color set it was a bit difficult : it has a bridge between two
connections of yoke's cable, to prevent functioning the tv without
h.d.y,with a piece of cable i make a jumper and made the same modifications
that i did to the b/w set... it's fantastic, it's not a real 'scope, it's
limited to 63Hz, but it's funny to see for the first time a signal
!!!!!!!!!!!!!

I.

 

[N Cook]

I made a simple scope with this metod :
I got from the scrap an old b/w set/monitor and another small color set that
didn't work well but there is HV !
I cut the wires to the horizontal yoke, on the b/w set I got a line across
the screen, well ! I turned off it. Then I connected the two wires of the
yoke to a simple bf amplificator ad injected an audio signal into the
amplificator. Immediately I seen on the CRT a glowing line, well, it's the
signal !!! Then I rotate G2s pot to get a more brighter line (the set was
junk... and i don't mind how it can last !)...
For the color set it was a bit difficult : it has a bridge between two
connections of yoke's cable, to prevent functioning the tv without
h.d.y,with a piece of cable i make a jumper and made the same modifications
that i did to the b/w set... it's fantastic, it's not a real 'scope, it's
limited to 63Hz, but it's funny to see for the first time a signal
!!!!!!!!!!!!!

I.

Another related piece of cobbled together test kit is a simple spectrum
analyser.
Take a TV tuner and a very basic scope display. Make up a sawtooth
signal generator and feed the ramp voltage to the X i/p and the tuning
Vt of the tuner and feed the tuner if o/p , high f rectified , to the Y i/p.
For added
sophistication loosely couple the o/p of a TTL crystal oscillator to
the tuner for spot frequency harmonics calibration.

Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

 

[Inty]

Another related piece of cobbled together test kit is a simple spectrum
analyser.
Take a TV tuner and a very basic scope display. Make up a sawtooth
signal generator and feed the ramp voltage to the X i/p and the tuning
Vt of the tuner and feed the tuner if o/p , high f rectified , to the Y i/p.
For added
sophistication loosely couple the o/p of a TTL crystal oscillator to
the tuner for spot frequency harmonics calibration.

Thanks for your interesting infos !!!

I.