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[TowerTalk] ATTN: Equipment Manufacturers who lurk here...

To: <cq-contest@contesting.com>
Subject: [TowerTalk] ATTN: Equipment Manufacturers who lurk here...
From: "Eric Hilding" <b38@hilding.com>
Date: Tue, 16 Oct 2007 14:03:45 -0700
List-post: <mailto:towertalk@contesting.com>
ATTN: Equipment Manufacturers who lurk here.


Yes, I'm picking on MFJ today, but have found similar product "Instruction
Manual" problems with other manufacturers who are willing to take our money
, but haven't walked-the-extra-mile to insure their "Manuals" are accurate
and complete.


Please, walk-the-extra mile with ALL your "Instruction Manuals".


Thank you.


Rick, K6VVA


(Sent to MFJ Customer Service)


I called MFJ Tech Support earlier today, but  was told it would be best to
email you for answers to my "Technical" questions about the MFJ-1708 RF
Sense Transmit/Receive Switch.


My purchase of TWO MFJ-1708's included "Manual" for each, which consisted of
one 8.5 x 11 inch pieces of paper folded over once.  On the front page under
the words "Instruction Manual", was the following:  CAUTION: Read All
Instructions Before Operating Equipment


Unfortunately, the "Manual" proved to be an exercise in futility and
resulting confusion due to erroneous wording and missing salient information
needed to effectuate an error free installation.


A. In the INTRODUCTION section, I found the read the following sentence:
"It {the unit} provides an auxiliary contact closure to ground during
receive (opened in transmit) for an "On-the-Air" sign or other use. This
makes absolutely no sense.  If a person were going to use an "On-the-Air"
sign, why would they have it light up during receive instead of during
transmit?  Please explain exactly how this device really functions.


B. No information is provided as to whether or not the "auxiliary
contact{s}" are simply separate contacts on the internal relay than can be
used to complete a 115v "On-the-Air" sign circuit, or whether this is
actually an internal 12v powered circuit for a 12v light <QLF snip> J


C. The additional sentence "It also has a control line input, which lets
your key/keyer or PTT line switch the antenna." fails to indicate if this is
a 12v line and what the current draw is.  Some of us combine control
switching functionalities with other devices, and it is imperative to know
exactly the specifics of a device we purchase like the MFJ-1708.  If I use
an Ameritron ARB-704 to key and Ameritron amplifier *and* trigger the
MFJ-1708 off the same line (assuming the "control line input" is, in fact,
as 12v pull-to-ground circuit), I need to know if the total current involved
will be within the maximum limitations for the ARB-704. Without the details
for the MFJ-1708, I cannot make an intelligent, informed decision before
potentially "blowing something up" ;-(


D. The manual further states: "An adjustable time delay circuit gives you
delayed switching.  This prevents your antenna from switching between dots
and dashes or between syllable and words."  (NOTE: in the subsequent
TECHNICAL DESCRIPTION section, it reads: "The delay adjustment allows you to
change how fast the relay switches back to the receive mode.  It is
adjustable from 0 to 2 seconds.").  What the manual does not state is if the
relay utilized is QSK operation compatible for those of us who intend to use
(at least) one of these units in a 35WPM CW "Search & Pounce" QSK mode of
operation.  Will the relay handle extended QRQ duration QSK?  I do NOT want
a "time delay" between dots and dashes, etc., I want QSK with one of the


E. In the TECHNICAL DESCRIPTION section I read: "The MFJ-1708 RF Sense T/R
switch requires 12VDC or 110 VAC with MFJ-1315 power supply."  Why isn't the
current draw listed?  My understanding is that MFJ-1315 is a 500ma supply,
but I need to know if the MFJ-1708 itself may only draw 100ma or 150ma,
because of the combined integration with other equipment items and a
different 12v power source  Why was this salient piece of information not
provided in the "manual"?


F. In the SCHEMATIC diagram, a connector/port/connection is shown and
labeled as "MUTE1".  I can NOT find any such item on the MFJ-1708 in spite
of checking the top, bottom and all sides.  Did I receive TWO units that
someone in manufacturing forgot to install something in?


G. Nowhere in the "Manual" is the maximum permitted transmitter power in
watts indicated for the MFJ-1708.  Is it 100 watts, 150 watts, 200 watts, or


I am not a technical guru nor a mind reader, and there are many other
amateur radio operators like myself who purchase equipment items expecting
clear, concise, detailed instruction manuals that are accurate and complete.
The "Manual" for the MFJ-1708 falls considerably short of the standard
expected of manufacturers in the industry.


Please clarify the above information  reissue a correct "Manual" for the
product to include a "Revision Date" and mail me TWO copies (for my TWO
MFJ-1708's) to my address on file.


Thank you very much.




Eric ("Rick") Hilding, K6VVA













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