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[TowerTalk] MFJ quality control

To: <towertalk@contesting.com>
Subject: [TowerTalk] MFJ quality control
From: "Jim Thomson" <jim.thom@telus.net>
Date: Tue, 3 Apr 2018 08:56:19 -0700
List-post: <mailto:towertalk@contesting.com>
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
sometime.    

##  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

Jim   VE7RF
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