Thanks for the note Bill. As you say, Physics doesn't cut any special deals with anyone. That of course is the good news delivered simultaneously with the bad news. The way to deal with radials is to
I am posting this on this reflector because I know a number of the readers [and writers] have the AIM-4170 . We also have some very brilliant thinkers and extremely competent experimentalists in the
This is pulled from a UHF-VHF reflector in MN-ND-SD-IA-WI. I have included the offer for sale of a General Radio 1606a RF bridge that many Topband folks have identified as a very useful piece of equi
Brad: I don't have time for a phone call this week. Here are a couple of suggestions 1. Go to my web site and look at the sections that deal with the MFJ-1026. Your 1025 is missing the preamp that i
A number of years ago I fabricated a very simple circuit to "delay" the "Key Down" signal sent to the transceiver slightly while allowing that signal to be sent to the amplifier to change the amplifi
Carl: I marveled at the number of ferrite cores as well when I first read the article. Re-reading it I think I found that he lived very close to an AM broadcast station which seemed to have common mo
I listened last night as TX4T called CQ for more than an hour with very few NA takers. He started just prior to 0600 UTC and was still going at 0700 UTC. He was on 1.8315 MHz and listening 5 Hz DOWN.
This is just a note intended to share some unexpected results. I have a K9AY pair of loops at right angles and also a pair of DxEngineering 102" active verticals. Both are used only for RX. The two s
I am organizing a large lot purchase of the Fair-Rite 2.4 inch toroid cores. If we can accumulate an order for 500+ cores we can capture a price of about $4 per core FOB the factory in New York. If y
Based upon the first day's email of commitments to buy, the price per toroid FOB New York is going to be $4.10 The datasheet for this toroid [core] is at http://www.fair-rite.com/cgibin/catalog.pgm?T
This is a follow up to Jim Brown's note on my measurements of choke impedance using a power meter. As Jim pointed out, the circuit he used on page 31 of his tutorial allows one to measure the impedan
Charles: I make 160 meter RF Chokes [Choke Baluns] by running six turns of coax through 5 cores of Fair Rite type 31 [2.4 in diameter cores]. Five turns and six cores will also work. Tod, K0TO I'd be
I have several copies of the General Radio 1606A RF Bridge manual that I would prefer to mail to someone rather than toss into the trash. These are copies of the original manual but very readable. If
Jim is correct. You can look in the ARRL Handbook for resistor combination that will give you the attenuation you desire while keeping the impedance at a suitable value. 73, Tod, K0TO with various At
This probably has a limited audience but I do know that there are some readers on this list interested in fabrication of high impedance common mode chokes for their stations. I built and measured 18
RonL A follow up to my earlier response with respect to measuring the chokes using an AMI 4170. This afternoon I measured two chokes with the AIM 4170 and ploted the results on the two cores, 4 turns
A couple rules for toroidal inductors might be useful. To increase the reactance you increase the number of turns -- the inductance goes up approximately the square of the number of turns. To increas
You are correct Carl, I should have inserted the URL's. My excuse, and it is pretty flimsy, is that I was drafting the reply on my iPad2 which is a bit harder to go off and get links on than my lapto
A trivial point in this discussion, but of some consequence in assessment of data, the average is almost always NOT the 50% point of a population. The Median is the midpoint -- that is 50% of the pop
I have operated a beacon on 186 kHz - - back in about 1999. I used a HyTower for the vertical element and then a loading coil to get it to match. Wait until you see what it takes to build a reasonabl