FIM-21/ 41 Repairs

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dd92251
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FIM-21/ 41 Repairs

Post by dd92251 »

The folks at Potomac Instruments almost always find something to repair /replace whenever you send your FIM in for Calibration. As many of you know the cost for this Calibration/Repair is pretty high. So, I'm wondering what seems to be the most common replaced/repaired part in these units ? ? ?

What have your experiences been ? Are the repairs & parts overpriced ?

I'm curious about your experiences...


Dave Dybas

( lets play nice and not rag on Potomac )
kcbooboo
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Re: FIM-21/ 41 Repairs

Post by kcbooboo »

My FIM-41 experience several years ago was horrible. They claimed my unit had been submerged in salt water. There was some light powdery residue on the IC sockets, around the star lockwashers in the chassis, and some green gunk around one capacitor lead. They apparently don't "fix" anything; they replace it with new because anything that leaves their factory must be in factory-fresh condition. The unit still worked however; it was all cosmetic and only looked poor on the inside. They claimed it could not be repaired and marked it "DO NOT SERVICE" in their database, so now I have an orphan.

When I got it back I cleaned the IC sockets and everything else, something Potomac refused to do, or claimed they didn't know how to do. It's still working except the variable caps aren't aligned with the dial and the CAL OSC won't correct the frequency error on the "B" band. I will have to "fix" it myself. Potomac's answer was to replace both tuning caps at a cost of nearly $1000, and replace the IC sockets and ICs on both boards. My unit was "so bad" they offered me a $3000 trade-in credit towards one of their new PI-4100 models. I just didn't have the spare $12,000 available for something I use a couple of times per year.

There are a few other companies that claim they can calibrate these units but apparently none are capable of aligning them to get the "B" band to track properly. I sent the unit to one place and they promptly shredded the factory box and sent it right back to me in their own box, saying they can't work on that equipment, even though their web page lists it as a unit they CAN calibrate. I tried contacting another cal lab and could never get to an actual technician to ask if they could work on it or calibrate it.

So as bad as it may seem, they really are the only game in town. There are other companies that can generate a standard field and put a sticker on the meter face, but they charge almost as much as PI does.

I also have an RCA WX-2A, RCA WX-2C, and Nems-Clarke 120-E. All of these work fine over the 540-1600 kHz range and indicate between 170 and 180mV/m on the 1V/m range for a local station, and that matches two other FIM-41 meters. The accuracy is either 1% or 2% depending on which spec you go by, and that's 10mV/m on the 1V/m range, so I'm certainly within spec. The RCA and Nems-Clarke meters have to be 60+ years old.

Bob M.
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Deep Thought
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Re: FIM-21/ 41 Repairs

Post by Deep Thought »

My experience (and those of others I am familiar with) is they really like to replace the rotary switches, variable capacitors and potentiometers. I have never seen one come back for "only" the $575-ish calibration fee...it is always at least $1000 more.

I understand the labor involved and the need to make at least some money on a very small market item, but using the repair service as a sales tool for a unit which costs 10x more is absurd.

Unfortunately, if you want to get it repaired, they own the ball, bat, field and umpires. I finally started checking the calibration myself; it is fairly easy to build a magnetic loop antenna rig and I calibrated that to one of my FIM-41s when it came back with a fresh calibration. The FCC doesn't seem to mind as long as there is a paper trail back to NIST.

I also bought one of the excess FIM-41s from the FCC equipment liquidation awhile back (the company still has some available for less than what PI will charge to repair one) and use that as my "quick-check" standard since it never goes into the field.
Mark Mueller • Mueller Broadcast Design • La Grange, IL • http://www.muellerbroadcastdesign.com
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RGORJANCE
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Re: FIM-21/ 41 Repairs

Post by RGORJANCE »

Having a senior moment here today...............I seem to recall a calibration service in Rockford, IL that did one some years ago, but can't find it at the moment. It I can recover the name. I will post it.

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Re: FIM-21/ 41 Repairs

Post by ChuckG »

RGORJANCE wrote: Mon Jun 29, 2020 12:17 pm Having a senior moment here today...............I seem to recall a calibration service in Rockford, IL that did one some years ago, but can't find it at the moment. It I can recover the name. I will post it.

Fossil

TMI Calibration Labs?
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Chuck Gennaro
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RGORJANCE
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Re: FIM-21/ 41 Repairs

Post by RGORJANCE »

Chuck:

That could be it. Although, I have this "Instrument Calibration Services" name rattlin round in dah noggin, hey. They could have changed names over the years.

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Re: FIM-21/ 41 Repairs

Post by Shane »

RGORJANCE wrote: Tue Jun 30, 2020 9:19 am Chuck:

That could be it. Although, I have this "Instrument Calibration Services" name rattlin round in dah noggin, hey. They could have changed names over the years.

Fossil
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kcbooboo
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Re: FIM-21/ 41 Repairs

Post by kcbooboo »

Mooretronix claims to be able to calibrate the RCA WX-2 series and the Nems-Clarke 120 series as well as the PI FIM-21 and FIM-41. I don't know how their service compares to what PI used to do, but it IS at least an alternative.

http://www.mooretronix.com/news.php

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Re: FIM-21/ 41 Repairs

Post by Deep Thought »

kcbooboo wrote: Tue Jun 30, 2020 11:55 am Mooretronix claims to be able to calibrate the RCA WX-2 series and the Nems-Clarke 120 series as well as the PI FIM-21 and FIM-41. I don't know how their service compares to what PI used to do, but it IS at least an alternative.

http://www.mooretronix.com/news.php

Bob M.
I thought Bob had shut down due to complications following his motorcycle accident. Is Mooretronix back up and running?
Mark Mueller • Mueller Broadcast Design • La Grange, IL • http://www.muellerbroadcastdesign.com
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Re: FIM-21/ 41 Repairs

Post by ChuckG »

Deep Thought wrote: Tue Jun 30, 2020 3:06 pm
I thought Bob had shut down due to complications following his motorcycle accident. Is Mooretronix back up and running?
I think he's been out of business for over a year now.
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