Genescope - What is it?

not much info on this piece of test equipment called out for in Sansui receiver alignment procedure ,

not for DNA testing, kind of a scope thing, no listings on evilbay, no wikiblurb,

thanks for any info!

cj

The picture is too fuzzy to read but perhaps a dedicated RF spectrum analyzer.

JR

PS: pass....

It is a sweep frequency generator plus a 'scope.

It displays the "frequency response" of RF/IF amplifiers.

Say AM radio. Start by injecting 445KC into the IF stage. The sweep runs say +/-15KC, 430KC to 460KC. Ideally the output is flat through the center, with fall-off on both sides. Diddle the IF cans for maximum gain and good symmetry. Check that you have a full +/-5KC of flat response (to +/-8KC for wideband, to +/-3KC for the usual cheap radio). Move to ANT and feed 600KC, then 1500KC, and adjust the RF stages for good gain and little sideband trimming.

On FM you want the discriminator curve symmetrical and kink-free out past +/-150KHz.

On TV you want smooth with small bumps out past 3MHz.

You "can" do this work with a low-geared RF signal generator and a notebook. Sweeping to a CRT is just faster.

Unless this is government work, or somebody has played with the trimmers, you really do not want to start the kind of job which needs a tank-sweep. The factory adjustments generally do not drift enough to matter. All analog radio is going downhill anyway.

FWIW: these things were never common in repair shops. I am sure I have never seen one powered-up.

Thanks you guys!  looks like a rf generator with hi speed scope

we have a Sencore SGG  165 and a scope so shine on the Genescope ,

doh, i get it now, gene is for generator, scope is for scope, probably designed by a guy named Gene so he put his name in there instead of Genscope, or not.

yes most of the receivers that come in  are lined up pretty good usually only a dial tweak is needed

easier to screw it up than make it better, Marantz used a heated enclosure for the 10B to simulate a hot chassis while doing the alignment,

Simpson ade a Genescope with a flip up irror for the scope,

edit: please insert an "m" where needed, keyboard needs a vacuum job, 

> with hi speed scope

I bet the sweep is the 60CPS power line, and the 'scope vertical amp does not have to be much faster.

It would normally read a "detected" voltage, either from the radio's own detector or maybe they give you a diode input.

yes it appears that every set comes with a 1n34, so the scope only has to do 60 for TV and 400 for radios,

poor folks had no freq counters,  life was tough back then,

car radios got banged around a lot, i bet they needed alignment now and then,

i wonder how many people made boot leg radios stations out of those Simpsons,

That's actually a decent solution for what people needed to accomplish back then, no? Never seen one in real life yet, sadly.

PRR said:

It is a sweep frequency generator plus a 'scope.

It displays the "frequency response" of RF/IF amplifiers.

Say AM radio. Start by injecting 445KC into the IF stage. The sweep runs say +/-15KC, 430KC to 460KC. Ideally the output is flat through the center, with fall-off on both sides. Diddle the IF cans for maximum gain and good symmetry. Check that you have a full +/-5KC of flat response (to +/-8KC for wideband, to +/-3KC for the usual cheap radio). Move to ANT and feed 600KC, then 1500KC, and adjust the RF stages for good gain and little sideband trimming.

On FM you want the discriminator curve symmetrical and kink-free out past +/-150KHz.

On TV you want smooth with small bumps out past 3MHz.

You "can" do this work with a low-geared RF signal generator and a notebook. Sweeping to a CRT is just faster.

Unless this is government work, or somebody has played with the trimmers, you really do not want to start the kind of job which needs a tank-sweep. The factory adjustments generally do not drift enough to matter. All analog radio is going downhill anyway.

FWIW: these things were never common in repair shops. I am sure I have never seen one powered-up.

Click to expand...

Hello PRR!
I have two Meguro msw 720d and 721d genescopes I am not sure how to use to calibrate fm and am receivers. Is there a manual or guide that I can follow to do this? I ask why you uploaded an image that already gives a call sign.
Hug!

This used to be called a "wobbulator". You may find indications on how to use it by googling it.

abbey road d enfer said:

This used to be called a "wobbulator". You may find indications on how to use it by googling it.

Click to expand...

Hello Albbey!
Virtually everything can be found on "google" but when it comes to genescope, there is none. Knowledge about it is getting lost, so I decided to ask here. Hug!