[TowerTalk] MFJ quality control
jim.thom at telus.net
Tue Apr 3 11:56:19 EDT 2018
Simply put, MFJ + Ameritron, Hy-gain and every company that they.... rescued,
DOESNT HAVE ANY QUALITY CONTROL.... PERIOD. None, doesnt exist.
I buy a MFJ clamp on RF ammeter..and although it works, I had to calibrate the damned thing.
The one and only calibration pot comes in one of 3 states.... fully CW, fully CCW, or somewhere
in the middle. It would have taken em all of < 10 secs to test AND calibrate it.
When you buy a new hy-gain yagi..and the tubing is not swedged correctly.... and either wont fit at all,
or is a sloppy fit, stop right there folks.
The money that MFJ LOSES from all the shipping and repair costs must be staggering. They just lost all
their meager profit margin right then and there. When 20-35% of their products get sent back, the time wasted
in opening up the box, sending it to correct dept, repairing it, boxing back up, shipping back out, endless e mails and
phone calls etc, they are wasting one helluva lot of time.... and $$$ .
## If the guy doing the swedging has the swedging machine setup up wrong, he ends up cranking out hundreds of
tubes that are either swedged too much..or too little. With a good process control in place, the bad tubing could be
quickly narrowed down to a specific lot number, date of manufacture..and employee responsible for the error. In short,
It should have never left the factory. Random samples should have been checked for fit and finish. The 1st 1-3 tubes should have
been checked, immediately after the swedging machine was initially tweaked for a specific production run.
## VE6RF buys himself an Ameritron AL-600 SS linear amplifier. Blows up within 2 mins. Sends it back. Replacement also blows
up within 3 mins. 3rd one also blew up. Turns out their was an air gap between final transistors and the heatsink ! wtf ?
The dealer simply kept sending out a new one..and repairing the old one.. WAY after the fact. The idea was to keep the customer happy,
so send out a new one asap.
## I know one fellow, who shall remain nameless, who is contracted out by a USA dealer, to open up , test, repair and rebox all the
Ameritron amplifiers the dealer sells. The dealer was getting fed up with the huge return on bad amps. The idea was to find and fix
the issues, before shipping it out. Otherwise, the damage caused by the poor build quality was insane. Tubes blown up, B+ supplies
blown up, SS final transistors blown to bits, bandswitches incorrectly wired, blown to bits. One bad connection on an EQ resistor that
sits in parallel with each electrolytic HV cap, means that cap gets the FULL B+ across it. 2800-3200 vdc will of course blow a 450 vdc rated
lytic into shrapnel. Then the flying shrapnel does even more damage with whatever it hits. Replacing a band switch is a night mare too, try it
## MFJ has always been a crap shoot, then Ameritron, and now Hy-gain and every thing else they handle.
## There is no way in hell they even test any of their products. They dont have a test program at all. They build it,
box it, ship it to a dealer..who re-ships to joe ham. Never seen a QC sticker or similar on an MFJ et all product.
Dealer repairs the defective unit in most cases. For MFJ to implement a basic simple QC testing and calibration
program would cost them very little. They would save a ton of $$. Eye ball the newly completed B+ supply. Then bring it up
slowly with a variac, using real low current fuses in each leg of the 240 line. Any defect, and the small value fuses will blow asap.
Find and fix the issue. Re-test, done. Then quickly do 100 more of em. No more blown up B+ supplies, and pissed off end users.
## These days, I advise folks to buy TWO of what they want from MFJ / Ameritron etc, then ship back the defective
unit that doesnt work. In some cases you might get two bad units. In rare cases you might get two good units.
## Just before I retired from the local telco, the company decides to replace all of its aging DC to dc power supplies. These
are the types that have -52 vdc going into them..and + 5 V @ 40A on the output side. Verizon shipped us 50,000 new
power supplies. Installed in the middle of the night, and tested 5 ways to sunday. We only did one half of the redundant
setup, then came back 3 weeks later to install the other half. The idea was not to install new supplies into both halves of a
redundant setup, in case both had problems and took down a piece of equipment. So each site required two visits, 3 weeks apart.
Each site also got spare new power supplies, and those too, had to be tested by stuffing into the various bays. Tedious process.
At the end of it all, we had ZERO bad supplies..and thats after being in service, with a full bore normal load running 24/7, after
2 years. I never sent one back for repair, even years later.
## also had to replace hundreds of expensive digital clocks used for timing digital spans, switching gear etc. They were $5000.00 each.
We only found one bad unit, just one. And never replaced any of the other several hundred units years later.
end of rant
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