Problem with Red Lion rotor tach display

Rick Martin

Gold Member
Joined
Apr 20, 2004
Messages
2,162
Location
BRADENTON, FLORIDA & FL10
Aircraft
Everglades Kite Gyro, Tandem Dominator
Total Flight Time
900 hours
Alright, electronics are a real weak point of mine.

My Red Lion display has gone crazy/dead. To my best knowledge the unit is 2-3 years old.

It has been working fine for many months. But the other day, during flight, it started displaying random numbers and changing back and forth quickly. During that same flight, it finally came to rest on 1428 and stayed. Then at Bensen Days, like a magician, Jake tapped it with his finger and it returned to "0" as normal. So I thought alright, I have a sloppy connection. when I had time, I opened the panel and looked, but did not find any poor connections. I even pulled the battery cover off where I found both "blades" still firmly attached to the lithium battery.

Sorry, I have not yet put a volt meter on the battery (I know, I know!)

Because the "blades" appear to be magically bonded to the battery, I'm guessing that the battery is not replaceable under normal circumstances

What I want to know is:

1. Were the two numbers, "1428" and "2", a code for a fault of some kind?
2. Is the described behavior indicative of a failing battery?
3. And if dead, can I actually replace just the battery

Thanks,
 
Alright, electronics are a real weak point of mine.

My Red Lion display has gone crazy/dead. To my best knowledge the unit is 2-3 years old.

It has been working fine for many months. But the other day, during flight, it started displaying random numbers and changing back and forth quickly. During that same flight, it finally came to rest on 1428 and stayed. Then at Bensen Days, like a magician, Jake tapped it with his finger and it returned to "0" as normal. So I thought alright, I have a sloppy connection. when I had time, I opened the panel and looked, but did not find any poor connections. I even pulled the battery cover off where I found both "blades" still firmly attached to the lithium battery.

Sorry, I have not yet put a volt meter on the battery (I know, I know!)

Because the "blades" appear to be magically bonded to the battery, I'm guessing that the battery is not replaceable under normal circumstances

What I want to know is:

1. Were the two numbers, "1428" and "2", a code for a fault of some kind?
2. Is the described behavior indicative of a failing battery?
3. And if dead, can I actually replace just the battery

Thanks,

I have used Red Lion meters quite a bit and the only problems that I've had were my own fault. The plastic case and guts inside does not like to be warped. The meters I use come with a spongy foam gasket with the case clamp. Check to see if the meter is clamped too tightly.

I know of no fault codes....you might want to visit their web site and check to see if there are any troubleshooting hints or links to such.
The units are fairly inexpensive and by the time the battery needs replacing you might want to consider replacing the whole unit.

I've never had to replace the battery in one. If you can determine the voltage try jumping another one across the one in the unit to see if the display winks back on. A regular alkaline should work.
Be careful of static charge. Ground yourself before touching internal parts.
 
Ray,
That is good advice, I would have told Rick to cut Jakes finger and attach to the case. Yours makes more since, but I like to keep things simple.
Jake ,what do you think?
 
Ray,
That is good advice, I would have told Rick to cut Jakes finger and attach to the case. Yours makes more since, but I like to keep things simple.
Jake ,what do you think?

That might work too.
But.........................
 
Thanks guys.
I'm at the airport now, so I'll give it a look (and of course I'll check the battery this time).
 
Hi Rick, I have sold dozens of the Red Lion tachs and found only two faults:

The battery is too big for the connector wires (tabs, whatever) and vibration can cause a wire failure.

On the units I sell, I run a bead of hot glue between the battery and the case to stop this.

I had one start making random numbers and freeze on a set. Red Lion warranteed it and returned the same unit in days.
The owner said it never worked right on his MAC gyro. We attributed it to Radio Magnetic Interference from the mag as it worked fine until the engine started.

I have replaced two batteries with batts from Radio Shack. Red Lion used a different battery back in the day of metal cased tachs.
 
Thanks Tom. Every bit of information helps.

The battery is still good (a stron 3V). All the dip switches are still positoned correctly. And the battery is still mounted very securely (didn't want to try to force it out). It appears that the 'Blades" might have pins at the bottom which push into the circuit board. I don't know if they are soldered in or not. The wiring connections at the back were nice and tight.

The display now reads 86 and is fixed there. I flew it three times yesterday but it just stayed at 86.

I will call Red Lion tomorrow.
 
No Title

Hello to all. I had joined he Forum last year and was taking lessons from Gary Neal, but then had to set my flying pursuits aside due to some family health issues. I am now in a position to get back to flying and have resumed my lessons with Gary. We are at the place where he wants me to taxi my single place Dominator and spin up the rotors, and get a feel for "balancing on the mains", without actually taking off. Problem now is, I notice my Red Lion DT8 rotortach is not working. No read out at all, which, I take it, suggests a dead battery.

I gather from posts I have read that I can either replace the battery or replace the whole tach (about $90), both of which require removing the current unit. I have taken a picture with my cell phone behind the panel, and it appears that the snug wiring harness will require removing the panel in order to access or replace the DT8. See attached pic. If so, how difficult is this to do? What tools are required, and what should I watch out for? Any suggestions would be greatly appreciated!

Thanks,

Russ
 

Attachments

  • photo127694.jpg
    photo127694.jpg
    80 KB · Views: 2
Rick: Are you using a reluctor pickup from an auto ignition system to count prerotator ring-gear teeth (the usual setup AFAIK)? The gap has to be incredibly small for the coil to register all the pulses. Of course the gap tends to widen over time. The least bit of out-of-round in the gear can result in an excessively wide air gap during part of the rotor's rotation cycle and a faulty (or no) readout.
 
Russ,

If I make it to the anson hangar this weekend, I will bring a red lion readout. We can swap the battery from my new one to yours to see if that clears your problem up.
 
Top