Bird 43 wattmeter woes

[n1pfc]

Is anyone having the same experience that I am with the bird 43 wattmeters?

My wattmeter does not always read correctly unless I smack the thing. I can generally get any reading I want by the number of times I smack it. It makes it hard for an inexperienced tech to actually tune an antenna especially when they can get everything from almost no reflected power to a massive amount of power depending on the number of times they smack the meter.

Thanks,
Kurt

[Jason]

Well, considering that the Bird Thruline has been about the most time tested and reliable wattmeter ever, your's is definately in need of a trip to the factory for a rehab.

A friend of mine came in third a number of years back when bird held a contest to find the oldest 43 still in service. I believe his was made sometime in the mid 50's. He's had it since it was brand new, and still works like a champ!

[tvsjr]

I believe you can order the movement separately as a field repair part. Otherwise, send it in... Jason's right, the 43 is absolutely the most reliable wattmeter ever built.

[stay-con]

My wattmeter does not always read correctly unless I smack the thing.

Please let us know what fixed it. Wheter it's some magic goo on the slugs or a trip back to the bird nest. One of ours at the shop does the same thing. You always get a funny look from the customers when you have to beat on the meter to get it to read right, then tell them, "Your antenna is bad."

Jeff

[kb0nly]

I have never heard of a problem where you had to smack it like that. My best guess, time to replace the meter itself, it's easy to take apart and replace it. There is just two wires to disconnect on the back.

Take a look at ebay, there was a guy on there selling new replacments for less than $100 shipped.

You can also get a replacement from Bird, but brace yourself on the price, at least that's what i thought the last time i checked.

[bernie]

My two bits worth:
I used to repair and calibrate these.
Obviously a new meter movement is the way to go, however it is often possible to repair meter movements.
I also save old meters in case I need to replace a glass.
Being a watchmaker also helps.
The meter used in the '43 depending on age and manufacturer may be a jeweled or taught band meter.
Taught band meters are simpler, however if the band is broken, the meter is un repairable.

The problem discribed suggests that there is a small steel particle stuck to one of the poles of the magnet, which interfers with the moving coil.

Remove the meter from the housing, carefully clean all dust from the meter case.

Remove the 3 screws on the rear of the meter, remove the movement from the front case.

CAUTION! the indicator needle is extremely delicate, as are the hair springs.

Inspect he meter hair springs. I have seen hair springs on meters get tangled due to a sharp blow.
The spring loops over one of the balance arms.

Gently blow across the meter so the needle goes up scale.
It would be better to use a watchmaker's bench blower, a desolder bulb would do.
Observe where the needle sticks, then inspect the air gap to see the obstruction.
It may be necessary to remove the meter movement from the back cover to get to the rear of the coil.

Use a sharpened tooth pick to move the chip to the face of the magnet where it can be easilly recovered.
Blowing Compressed air in the gap is not likely to clear the problem permanently as the chip will eventually jam the meter unless removed.

Do not seperate the coil assembly from the pole magnet, damage to the coil is likely.

Line section.
Dissemble for inspection, remove the QC connectors, inspect center pins, replace if broken, or worn.
Remove the contact assembly.
Strighten the contact so it has no bends or twists.
inspect the rivit on the connector, it may need to be re soldered.
Clean the plastic spacer, re assemble.

Elements can often be repaired, and re calibrated.

The bits and peices for the case are still available from Bird.

[440roadrunner]

In addition to all the above, how did it get that way in the first place?

Dropped numerous times?

Banged around up and down roads to mountaintops?

Banged against the needle with a slug too low in power?



Do you religiously turn the slug 90 degrees to short the meter, and dampen it's movement?

[tvsjr]

Do you religiously turn the slug 90 degrees to short the meter, and dampen it's movement?

Explain this one... you mean for storage? Personally, I reinstall the dummy slug...

[440roadrunner]

Not so much for storage, as protection in transit---turn the slug so the arrow points up to the meter, and this shorts the movement, dampening it's movement. You can see this easily, just by "swaying" it by hand back and forth.

[commtek]

I agree with Bernie, but I would look at the connections in the line section first. I had this same problem with my 43 as it grew older and that was the fix.

I also agree with turning the slug 90 degrees for transport.

[tvsjr]

Not so much for storage, as protection in transit---turn the slug so the arrow points up to the meter, and this shorts the movement, dampening it's movement. You can see this easily, just by "swaying" it by hand back and forth.

Learn something new every day. Does the dummy slug (all metal body) have the same effect?

[commtek]

Yes, as it shorts across the meter movement. Makers of VOMs like Simpson usually do this when the meter is turned off. It shorts the meter movement.

[tvsjr]

Interesting. I'm a child of the digital age, but I still like my Bird 43 and my Simpson 260. I guess I'm doing the right thing by reinstalling the dummy slug (I also put the covers on the N connectors...)

[Nand]

My wattmeter does not always read correctly unless I smack the thing. I can generally get any reading I want by the number of times I smack it.Kurt

When you smack me enough, I will also tell you anything you want.

One of my 43's ended up with condensation in the bearings that froze in the winter, resulting in no reading at all.

Nand.

[wavetar]

We have an old Bird meter which seems indestructible, but we have had nothing but problems with the new Bird meters. Purchased 6 of them a couple of years ago & every one of them has crapped out...multiple times. We've sent them back again & again. They've been replaced & sometimes 'repaired' with no real fix. I've now taken it upon myself to strip each one down, clean every contact & reassemble them. They'll generally work for a few months then require it again. These things are not abused, they still look nearly new. They don't make 'em like they used to, that's for sure.

Todd

[n1pfc]

I have never heard of a problem where you had to smack it like that. My best guess, time to replace the meter itself, it's easy to take apart and replace it. There is just two wires to disconnect on the back.

Take a look at ebay, there was a guy on there selling new replacments for less than $100 shipped.

You can also get a replacement from Bird, but brace yourself on the price, at least that's what i thought the last time i checked.

We tried replacing just the movement a while back and the same problem resulted yet again within a couple months. And it's not just one meter that does it. We have multiple birds you have to smack to get to read correctly.

Kurt

[n1pfc]

In addition to all the above, how did it get that way in the first place?

Dropped numerous times?

I'm sure they've been dropped, but not all that often. I'm usually pretty careful about not dropping them and have yet to, but I'm not sure about the other techs.

Banged around up and down roads to mountaintops?

They're usually mobile in the repair vehicles, but stay in one spot. They're not flying around the van like a bird in a cage (pun intended)

Banged against the needle with a slug too low in power?

100W slugs only. If we know we're close to the max on a slug (X9000 or maratrac w/ 100W slugs) we generally just key the radio for a second and make sure the needle goes past 90W. We dont leave it sitting on the pin for any length of time

Do you religiously turn the slug 90 degrees to short the meter, and dampen it's movement?

Never even thought about that one. I'll have to try that and see if it improves the meters at all. Usually the last slug we used in the last position used ends up staying in the meter as it's driven around town

Kurt

[Will]

The original meter movements were made by Phastron in So. Pasadena. Phastron is no longer in business, and no one could make a better meter. But allong came Digital meters...

[davco3]

If you have female UHF connectors on a BIRD 43, these get cold solder joints on the center pin interface. Take a flash light and look down, and see the black circle in the middle of the female center pin. The fix seemed to be wacking the meter whenever I had this problem. New connectors from BIRD, and think about ordering a different type of connector like N.

On the new meters, check the connections to the Meter! I have had them come loose, a resolder job fixed it.

Be nice to your meter movements, and they will be nice to you.