Heathkit Analyzer question

[ModAfan]

I bought the CO-1015 Heathkit Ignition Analyzer in the photo on eBay last week. The seller said it was built by his grandfather in 1976 and used very little. It looks new, calibrates perfectly and came with both the Assembly Manual and the Operation Handbook. Can anyone who uses one of these analyzers tell me if there are any considerations in its use on the Model A ignition system, other than swapping the red and black leads because of the Model A’s positive ground?
Thanks.

 

[Tom Wesenberg]

On the inductive pickup that fits on #1 plug wire, I found it won't work unless you slip some plastic tubing over the brass strap. I slipped some thin clear plastic tubing over mine.

 

[ModAfan]

Thanks, Tom,
Do you agree with forever4 that: "I definitely would not swap the positive and negative leads."
If the car has a positive ground, how could you not connect the red lead -positive - to ground?

 

[Y-Blockhead]

...other than swapping the red and black leads because of the Model A’s positive ground?
Thanks.

As I read your question you were asking to swap the red and black leads i.e. red to black, black to red. I suspect forever4 read the same. (I could be wrong). Just keep red(+) to red(+) and black(-) to black(-), regardless which is ground and you should be fine. As long a the box itself isn't grounded it won't care.

 

[BILL WILLIAMSON]

Anyone ever done this: Bought a METAL DETECTOR kit @ Radio Shack, assembled that dude & the blasted thing didn't work! Re-checked EVERYTHING! Took it back, wearing an OLD shirt & an OLD hat, limped more than usual, & they gave me an identical FACTORY ASSEMBLED one, FREE! It WORKED!
Bill W.

 

[Tom Wesenberg]

Anyone ever done this: Bought a METAL DETECTOR kit @ Radio Shack, assembled that dude & the blasted thing didn't work! Re-checked EVERYTHING! Took it back, wearing an OLD shirt & an OLD hat, limped more than usual, & they gave me an identical FACTORY ASSEMBLED one, FREE! It WORKED!
Bill W.

I assembled one in the 70's and it worked OK. It was very basic though and couldn't discriminate a gum wrapper from a gold watch. All I ever found was a small bit of loose change in the grade school playground.

 

[Tom Wesenberg]

Thanks, Tom,
Do you agree with forever4 that: "I definitely would not swap the positive and negative leads."
If the car has a positive ground, how could you not connect the red lead -positive - to ground?

I'd have to do a search for the scope picture I posted here years ago. If the scope picture goes down instead of up, then switch the leads, or does your scope already have a switch for positive and negative ground?

 

[ModAfan]

Tom,
There is no polarity switch. I finally read the manual. It says a positive ground system will produce a primary pattern that is inverted from those shown in the Operation Handbook (negative ground patterns). “The secondary patterns will be the same for both negative and positive ground systems.”
The manual doesn't say the positive lead can't be connected to a positive chassis. I will try it out of curiosity to see if the primary patterns will be the same as they are in the handbook.
Thanks again.