![]() You also could check Surplus Sales of Nebraska to see if their parts suit your needs and purse. You may have these in your junkbox or from a hamfest to get an old buzzard look like mine. 22 uH Air Roller Inductor as used in MFJ-989D ($54 EACH)ĭepending on what you want in style, the turns counter and crank and reduction tuning knobs and indicators are all available from MFJ also.Here are the parts to roll your own if you still want to: Buy the best separate pieces, roll your own, I think. The Heathkit SA2060 is the same antenna selector. The antenna selector inside the TT 238 is a cheap rotary switch, not an Alpha Delta. See my article on rebuilding a burned out 238B for the inside story. It has a much better matching range than the Ten Tec 238C which is $819. You even get a small 300 Watt dummy load. For the price ($410), all assembled, it packs a lot of features and value into one box for a good price. If it fails, you can replace it without having to do it inside the antenna tuner box with expensive proprietary parts. The plating rubs off and the contact resistance becomes intermittent and high because the base metal is not reliable any more. Any of them employing a leaf switch in a machined housing are better than a conventional ceramic rotary design as used in the MFJ-989D or the old Heathkit antenna switches. There are Daiwa, which are pretty good, and MFJ and Diamond. The Alpha Delta antenna switch is without compare. I was able to get good correlation between my digital wattmeter and the TT 1225, unlike the eham reviewer who complained. The Ten Tec power meter kit is pricey at $160, You can also get a fully built and calibrated one of various brands for similar prices. If you already own these items, why pay for them again? Just build the tuner in a separate box, which is the best way, IMHO. That includes an antenna selector (I prefer an Alpha Delta Switch for reliability) and a power meter (I prefer a separate power meter like the Ten Tec KIT #1225). This is half what you would pay for the full MFJ 989D. If you cannot obtain the parts surplus or at hamfest, you can purchase those employed in the MFJ-989D brand new directly from MFJ for less than $200 total. A minor improvement inĮfficiency on 10 and 15 meters was observed. I addedĬoax RG-8/U on the input and output connectors to the tuning capacitors toĮliminate inductance in series with the capacitors. ![]() This prevents damage to the roller inductor or transmitter. With the roller inductor to ground to prevent adjustment of inductance to Transmatch with the Valiant on higher bands. Satisfaction of creating your own equipment.Īfter a test run with the new K7DYY transmitter, I also used the new You will save a lot of money and get some Yes YOU can build a transmatch just as nice as any commercial unit if you The turns counter and capacitor vernier knobs are from WW2 surplus.Įven though the new rig is modern, I still like a vintage look for the ![]() Be sure to get one with heavy wire to handle the power. The roller inductor is 26 uH but you could probably make do with 20 for 160 The input and output capacitors are 500 pF. Iīuilt this in two days from items I had in my junk box. K7DYY AM transmitter for 160 and 80 Meters. This is the homebrew Murch style transmatch I built to work with the new Dials and knobs are all WW2 surplus from my junkbox. I had a nice 19" rack cabinet and like to work with sheet metal. Be aware of shock hazard if you leave it on a simple horizontal wooden "breadboard" style. ![]() You may want to use wood for the case, if you are handy with that medium, to save cost. What is the best full legal limit transmatch, antenna tuner available? The one you build yourself.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |