bflynn
Final Approach
And once solved it will become a trivial and boring problem.
The amazing cryogenic JPI EDM 930
- Thread starter Katamarino
- Start date
Katamarino
Pattern Altitude
Let's hope.
Katamarino
Pattern Altitude
Only the OAT wires. We have checked them for correct continuity.
Katamarino
Pattern Altitude
I believe we did; the ground strap is properly installed and we have confirmed good ground continuity between engine and airframe with less than 0.5 ohm resistance between any points.
Ed Haywood
En-Route
Might want to undo the strap and brighten up the contact surfaces on both ends. Can't hurt.
Half Fast
Touchdown! Greaser!
@Katamarino Any news?
Katamarino
Pattern Altitude
None yet really - I was traveling the last few days and JPI have not replied to me email asking for an update. I will try and call them tomorrow.
I did fly a lot over the weekend. The behaviour continued to be intermittent. On one of 6 flights, it worked perfectly. On two flights it barely worked at all. On the remaining three it worked properly over 50% of the time.
Half Fast
Touchdown! Greaser!
I guess it's intermittently intermittent.....
Ed Haywood
En-Route
Intermittency makes me think of loose things vibrating.
JOhnH
Touchdown! Greaser!
It makes me think of our old tube type TVs.
Give it a good smack and see what happens.
Pugs
Cleared for Takeoff
You skipped pulling tubes and going down to the drug store to use the tube testerIt makes me think of our old tube type TVs.
Give it a good smack and see what happens.
JOhnH
Touchdown! Greaser!
I had my own tube tester. I often fixed friends and neighbors TVs. First diagnostic was a slap. If that helped I assumed a tube was flaky and brought out the tube tester.You skipped pulling tubes and going down to the drug store to use the tube tester
Sometimes while pulling tubes I would see a blown capacitor or resistor. If it wasn't tube or a visible issue, I gave up. But most of the time I was successful.
Often people would give us their old non-working TVs. My younger brother and I would take them apart, piece by piece and sort and store tubes, capacitors, resisters, power supplies etc. We took up most of the family room with our work bench. We often had a good part on hand to fix most tvs or radios. It was a fun way to pick up a little spending money.
Ed Haywood
En-Route
You skipped pulling tubes and going down to the drug store to use the tube tester
And fiddling with the rabbit ears antenna. Aluminum foil sometimes helped, for mysterious reasons.
Half Fast
Touchdown! Greaser!
I recall my dad up on our roof, turning the antenna and yelling down to me “Is that better? How about that?”
Yes...it keeps the NSA from altering mind waves.....
Oh...nevermind...foil on the antenna..oops.
guest user
Line Up and Wait
- Joined
- Dec 16, 2021
- Messages
- 978
- Display Name
Display name:
just passing through
Reading through this makes it almost certain to be a grounding issue.
1) The system has worked as expected, so no wire polarities are reversed.
2) The broken times affects ALL probes at the same time and to the same degree. Only thing they should all have in common is the ground wire.
This is going to be an interrupted ground issue. It could be that the ground path is fine but that something is vibrating to be in contact with the ground path messing it up. So when you look at the ground wires and connectors they are fine, but it is really something nearby causing the issue.
As previously stated:
1) The system has worked as expected, so no wire polarities are reversed.
2) The broken times affects ALL probes at the same time and to the same degree. Only thing they should all have in common is the ground wire.
This is going to be an interrupted ground issue. It could be that the ground path is fine but that something is vibrating to be in contact with the ground path messing it up. So when you look at the ground wires and connectors they are fine, but it is really something nearby causing the issue.
As previously stated: