Heathkit Colorbar and Dot Generator Model IG-28: How do I use it?

[vortalexfan]

Hello everyone, I recently acquired a Heathkit Colorbar and Dot Generator Model IG-28 from a local flea-market for $5 and I was wondering if there's anyone on here that can instruct me on how to use it, or that has a manual they can scan and send me? I was attempting to use it last night to try and work on my 1967 Sylvania Color TV that I am trying to fix up but I'm not sure if I'm using it correctly or not. Unfortunately no one has a free download of the whole manual for this unit because of copyright issues supposedly (which I'm not sure how there could be copyright issues when the Heath Company went bellyup over 35 years ago after it was acquired by Zenith, but then when Zenith went under after it was acquired by Goldstar (LG) I wouldn't think anyone has claimed any copyrights to Heathkit stuff anymore.)

This Colorbar and Dot Generator has 2 sets of cables coming out the back, one set is a two conductor RF Signal Output for hooking the generator up to the tuner of the TV via the antenna inputs on the back of the TV, the other set of cables is a 4 conductor cable with wires marked Red, Green, Blue, and Ground (Black), and those cables are supposed to be for hooking directly up to the Red, Green and Blue Grids of the Picture tube with a ground conductor
and I'm unsure how that would work. Also when I tried to use the built in tuner on the generator for matching the output signal of the generator to the output of the TV it acts like its not outputting the correct channel at the spot its supposed to (like channel 3 for instance is showing up on the bottom end of where channel 2 is on the tuner dial on the generator.)

Anyways I could use some assistance in figuring out how to work this thing since I've never used one of these before and I would like to try and utilize this for working on my vintage TVs if I ever need to work on them.

Thanks for your help.

[Electronic M]

I've had a few of them. Only the 2 wire clip leads have signal. The 4-wire cable is for the gun killer switches which are only useful when doing purity adjustments (they let you adjust purity without having disturb the grey scale pots), also there's a version of this generator that's combined with a vector scope for doing chroma demodulator alignments and the input to the vector scope is the 4-wire interface. I never hook up the 4 wire cable.

RF output isn't always dead nuts accurate. If you can get it tuned in ok then it'll be fine.

These units have a penchant for developing dirty IC sockets. If things are missing from the pattern you may need to reseat the socketed ICs. Besides the 3 bar/9 bar pattern switch and the switch that swaps output between video and RF (and the video pot not effecting RF) the controls are fairly intuitive/self explanatory without a manual.

[kf4rca]

You should add this mod to your IG28 if it has not already been added. It prevents the wagging of vertical lines at the top of the frame when in crosshatch mode. I added it to mine and it works.

[Kevin Kuehn]

Originally Posted by kf4rca

You should add this mod to your IG28 if it has not already been added. It prevents the wagging of vertical lines at the top of the frame when in crosshatch mode. I added it to mine and it works.

Interesting. I had a similar issue with my IO-101, same pattern generator board I believe. I was able to fix mine with a single resistor.

Here's my documented adventure. https://videokarma.org/showthread.php?t=268858

[kf4rca]

I was surprised how much some of these Heathkits go for. You might as well go for the Cadillac of test generators:
https://www.ebay.com/itm/18562993094...Bk9SR5bl9JzzZg