Retired
The BLT is a simple Z-Match tuner that works from 10-40 meters, designed by
Charlie Lofgren for NorCal. Charlie
is probably the number one man in the world when it comes to Z-Match Tuners,
and he has designed this one especially for NorCal.
The tuner tunes balanced feedlines, thus the
name "BLT" for Balanced Line Tuner for the mnemonically-challenged among us.
Charlie originally designed the tuner to go with the SMK-1 and the NorCal
Doublet for 40 meters, but when he delivered his design we found it tuned
other bands also. With the NorCal Doublet, it tunes 10 - 40 meters.
We rate the tuner at 5 Watts, but it will probably be safe at 10 W.
It comes with the Dan Tayloe N7VE LED SWR indicator built in, and is
an absorptive bridge, so you won't fry the finals as you tune.
Great design, by a great designer. All parts for the tuner are included,
including the case. It uses polyvaricon caps. There is already a mod to
convert it to end-fed wire and coax. All you have to do is add one BNC and a
SPDT switch, and you can use end fed wires and coax antennas. The connectors
included are two 5-Way Binding Posts for the balanced feedline, and a BNC to
connect to your rig.
Download the "BLT Tuner
Construction Manual" (with active hyperlinks!) -- 1 MB
We used to supply some copper-clad material
for a case and a clear plastic top half for the BLT Tuner Kits. But
after several years of producing the kit, I have run out of the clear plastic
covers, so I decided to investigate the possibility of using an aluminum
case. I checked with Ten-Tec, even ordered some of their TP-15 cases
to try out. I wanted to make sure that the tuner would still work okay -
and it does! Walter Dufrain, AG5P built a tuner using this metal
enclosure approach, did some extensive testing, and reports that all is
fine. Well, I thought that I could get a custom case made and it
would be predrilled, which the Ten-Tec case would not have been. Several
guys have told me that the hard part of building up the BLT was the case,
and that they wished it would come in a case of its own. I thought about that,
and decided to see what I could get done.
So I went to San Jose and
contacted several sheet metal places and finally found one that would do the
job ... The BLT is now packaged in a .062 aluminum case, clam shell style,
front and back panels predrilled, and will be held together with counter sunk
flat head screws and PEM nuts. The size is 3" x 3"
x 1 5/8". Front and back panels are 1.5". Think of the case
for the SST and you'll get the idea.
I also decided that we need a pc board to replace the Manhattan style
construction used in the old tuner.
We now supply a Pittsburg Style Board
. Pittsburg style means that the pads and traces are etched on
the board. All that you have to do is put the parts on the board and
solder. The layout is already there, and no pads to glue down.
"Got mine finished last
night and never have I had a kit that I put together work the first time.
The BLT tuner worked great. Just had the diode in backwards but that was
easy to fix. Doug has made one of the best manuals for a kit that I have
seen. Photos are great and sure help you keep on track. This kit would be
great for the first time builder. It was great to see the LED go out on 40
meters. Doug you have set the standards for a user manual.
A big thanks!"
... 72 Gene N0MQ
NorCal BLT Tuner .... with new aluminum case (shown on left)
(Inside of Tuner shown on right with older-style case)
Jerry Haigwood, W5JH
created these PANEL LABELS that can be attached using 2" clear box
tape.
He uses an Exacto knife to cut out the holes for the
components. Components also help hold the overlays on the
panels. The overlays will give the BLT a finished professional
look!
(Download a PDF file containing actual size color
overlays)
This kit can be orderded through Doug Hendricks
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