Copyright © 2002-2019 by Harold Melton, KV5R. All Rights Reserved. Rev. 02/19/19.
A heavy duty 2 core balun is included for open wire or single long wire operations. A selector switch on the front panel allows selection of an alternate antenna (or dummy load), bypass, coax, single, and balanced. Power handling capability of the Super Tuner Plus is 1 KW CW and 1200 Watts PEP SSB (both measured in DC input to the final amplifier). A brand new, never used, still in original shipping box Bird Model 43 wattmeter with warranty card, manual, and original box. $325 plus shipping / Also Dentron Super Tuner Plus Antenna tuner,excellent condition, no arc, works like a new tuner $240 plus CONUS shipping only.no palpal, postal checks are ok, thank you, Dave WD8PBF. Dentron Super Tuner Plus Manual 11/3/2019 Using the Power Step once or twice a day for between 10 and 15 minutes is the equivalent to one hour in the gym and can burn up to 400 calories. WELLNESS Power Step Plus enables not only an athlete or those in need of physical therapy to enjoy the benefits of using vibration exercise.
Entry: Feed-Throughs and Lightening Arrestors
How to make your own spark-gap shunt (“lightning impulse arrestor”), waterproof ladder-line feed-through, and quick-disconnect for (hopefully) improved lightning safety, using common hardware. Or, how to possibly avoid the “billion-amp arc in the shack” scenario.
Disclaimer: All disclaimers apply. No guarantees. I am not an engineer nor expert in the field of lightening protection. I assume absolutely no liability for your use of this material. These ideas have not been tested. Use at your own risk! The actual effectiveness of these measures cannot be quantified. Lightning is dangerous, destructive, deadly, and unpredictable, due to rapid release of incredible power, and extremely wide range of variability.
My HF antenna is a 160 meter dipole, fed with 14-gauge windowed ladder-line. This arrangement should make a nice lightning collector, so I took special precautions on the entry path of the ladder-line.
In figure 1, notice the PVC standoff (one of two), made of half-inch PVC, about six inches long, attached to the trailer with aluminum angle. The ladder-line proceeds down to the arc-shunt assembly, which is mounted directly on the ground rod. It then proceeds up to brass feed-through assemblies (Fig. 2). Once inside, it plugs into the tuner with banana jacks (Fig. 3), for quick disconnection.
The ladder-line is kept separate from all the other cables, which enter via a 1½-inch PVC nipple and coupling (inside) through the floor. The coupling is packed with paper towels (and a little boric acid powder) to keep out bugs. The arrangement provides a good seal that can be easily removed and replaced to allow passage of PL-259s intact.
2018 Update
In the spring of 2018 I went QRO, and put up a heavy-duty 80-meter doublet, fed with 4-inch open-line. I made three different entrances: (1) Wires through tubings through the wall; (2) twin coaxes through the wall; and finally, balun outside and coax through a bulkhead fitting in the wall. All worked well, but I like the last one best, for several reasons.
Please see 80-Meter Doublet in the 2018 section. Lots of pictures!
Continued…
Ladder Line Page 3 — Ladder Line Page 5
I purchased this nice little 100 Watt CW or SSB PEP class antenna tuner at a swap meet as a gift to a friend, to use with his Yaesu FT-450. If he inherits my DX-40, it will likely be fine with that, or a barefoot DX-60 too. But I doubt it will handle a 100 Watt AM rig like the DX-100. Damage to the plastic coil may result with full duty cycle full carrier 100 Watt AM. The capacitors may arc. The internal tuner in the FT-450 will not match more than a 3:1. This manual tuner extends the range to work with an end fed wire, G5RV, open wire fed doublet, or the band edges of a standard 80 meter dipole.
MFJ likely would have advertised this tuner as a 300 Watt unit. Some similarities to the Johnson Matchbox JR 275 watt tuner can be drawn, and perhaps I am being too conservative in my speculation on power rating. Later versions of the Dentron unit shown here may be built for more power.
As I received this tuner, the left hand capacitor was wired as a sort of 'voltage divider' similar to what is used on the output of the Johnson Matchbox JR. This does not match the schematics on the website listed below. I modified the one I had to match the later version of schematics he shows.
Dentron Super Tuner Plus Manual
Schematic and Manual (2 pages). Thanks to W4DEX for the info:
Disconnect the wire shown by the pointer (wooden barbecue skewer) from the ground lug near the front panel and attach it so that both of the stators (stationary plates) on the left hand capacitor are connected together. This new wire does not attach to the bottom of the coil, it just is a splice, up in the air over the lug that supports the coil. Sorry if this photo is confusing, but there is not much room in this compact tuner. (IMPORTANT: LEAVE THE EXISTING WIRE FROM THE COIL SWITCH ATTACHED TO THE GROUND LUG. Just disconnect the wire to the capacitor.) This increases the total capacitance available, making for better range of matching, especially on 160 meters. Note that this modification is actually the way Dentron did it in later production models of this tuner. It matches the schematic shown above. Tuning in this configuration does not seem to be touchy, and it makes a good match on all bands 160, 80, and 40.