Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Thu, 24 Mar 2011 10:01:08 -0600
Tentec has the X ray picture of the PC board with component silk screen. Its needed with the schematic and with much trouble and guessing could be traced to make a schematic. 73, Jerry, K0CQ At the v
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Thu, 24 Mar 2011 11:41:46 -0600
Best I can tell, remoterig only remotes a few radios without a control computer. Those rigs use a serial interface to a removable front panel and allow for time delays between commands and responses
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Sat, 26 Mar 2011 13:52:09 -0600
Is the rig RS-232 or is it TTL? If you have to use a level converter from the computer serial port its sure the rig is TTL, like most ham rigs using CAT especially Icom which the Tentec seems to be c
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Tue, 29 Mar 2011 15:45:56 -0600
The manual for the FT-901DM is available at http://bama.edebris.com/manuals/yaesu/ft901dm/ which is often a prime source of manuals. There is a yaesu forum, at least one of them is at: Yaesu mailing
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Wed, 30 Mar 2011 09:31:01 -0600
http://www.w4qcfmanuals.com/manualsTA-TG.html lists the 2510 for a price. http://ac6v.com/manuals.htm has a long list of manual sources, free and paid. But only QCF admits knowing a 2510. I'd think i
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Thu, 31 Mar 2011 13:49:42 -0600
There are wattmeters from Collins, MFJ, Comet, Yeasu, Icom, Kenwood, Bird, and myriad other makers that are not dependent on a particular brand of radio, often with better precision than simple coupl
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Wed, 02 Feb 2011 17:27:49 -0600
Sometimes that kind of fan can be lubricated, but its difficult. The bearing is hard to get to. Sometimes a cross cut at the middle of the label allows injecting a bit of oil. Hope that the oil you i
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Thu, 03 Feb 2011 16:30:44 -0600
That slow change of the resistive component and rapid change of the reactive component is much more prominent if you look at the parallel admittance than the series impedance. 73, Jerry, K0CQ When yo
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Thu, 03 Feb 2011 16:37:45 -0600
And when you fatten the antenna you only need to fatten the ends for most of the effect. One time I fanned out the ends of an 80 meter dipole with great effect. Added a second wire about 6' from the
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Fri, 04 Feb 2011 03:46:33 -0600
The best reports I've seen published on broad banding antennas is in the two volume set, "Very High Frequency Techniques" that was a report of WW2 work at the Radio Research Lab at Harvard. Edited by
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Fri, 04 Feb 2011 03:47:22 -0600
Good luck. 73, Jerry, K0CQ That slow change of the resistive component and rapid change of the reactive component is much more prominent if you look at the parallel admittance than the series impedan
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Fri, 04 Feb 2011 10:11:37 -0600
The DSP noise blanker may be as susceptible to nearby strong signals as the hardware noise blanker. 73, Jerry, K0CQ Thank you for your helpful responses. Indeed it appears that it is my unfamiliarity
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Fri, 04 Feb 2011 12:20:39 -0600
Noise reduction is a totally different process than noise blanking. Noise blanking is for short and very strong pulses like ignition and power line noise. The noise blaker, whether hardware or softwa
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Sat, 05 Feb 2011 10:35:42 -0600
Those all work if they have good voltage regulation to not overcharge the batteries, but the low current chargers and battery tenders probably won't keep up with conversational use of the amp. Maybe
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Sat, 05 Feb 2011 15:01:12 -0600
According to the Herc II manual it draws 80 to 100 amps for 1 KW input. Batteries last even better if the discharge is less than 50%. 73, Jerry, K0CQ You are asking what kind of battery capacity you
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Sat, 05 Feb 2011 17:51:04 -0600
I think the Trojans are about 120 ah. So they in theory would supply 80 amps for 90 minutes continuous. Longer loaded time if loaded intermittantly. But they survive much longer if less than half tha
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Sat, 05 Feb 2011 19:44:35 -0600
That's a working scheme if you have the space. Probably would work with only a 6 or 8 foot space at the ends too without having to be at right angles. But the smaller fan angle might require a bit of
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Sun, 06 Feb 2011 00:47:10 -0600
Near the feed point its mostly magnetic coupling, but at the outer ends its mostly capacitive coupling. The fanning idea is more effective the greater the spread out to at least 30 degrees fan angle.
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Sun, 06 Feb 2011 01:28:02 -0600
Inductive coupling IS magnetic coupling. 73, Jerry, K0CQ When you say "magnetic"... I take it that is the same basic concept as when one talks about magnetic fields surrounding current in a wire --us
Author: "Dr. Gerald N. Johnson" <geraldj@weather.net>
Date: Sun, 06 Feb 2011 10:22:18 -0600
There's a slight chance the value is stamped on the pot metal case. If its 250k and you put in 500K, you extend the LF range of the notch by a factor of 2 and make tuning more critical. If its 500K a