I have a Yaesu FT-817 which operates at a lower power output (about 1.5-22.0 watts) even when the power is switched on to maximum (three bars). This happens only on the 2 meter bands. At HF frequencies and on 440, the unit puts out full power when switched to maximum. I've connected several  different antennas (thinking it might be high SWR fold-back), including the accompanying duck, a Ringo Ranger and an external car mounted antenna: same behavior. Is there an internal setting that I'm overlooking?

Many thanks from you -817 owners out there. 73 Tom NY2RF

You have a good earth ground (driven rod into the ground) when the voltage difference between your home 120 VAC hot wire (black) and your earth ground is 120 vac. That's evidence the ground is providing a low resistance path for the AC.

I have a 3-element beam for 10 meters on my mast And I would  like to add a six meter yagi above it. What's a reasonable separation distance between the two antennas? I recall the half wave length rule using the higher frequency. It may just be folklore or myth; or merely my failing mental faculties.

73 Tom

Replies were helpful. What's the difference between an AH-4 and an AH-140? The 140 is still sold for between 460 and 471.00. I looked at one today on a Coast Guard installation: it was 50 percent larger than my AH-4.

Tom N4GRF

Here's the schematic for connecting a David Clark to power up the internal amplified mike. Just connect to your ICOM and use the +8 volt supply voltage to power the mic.This solution works: I just installed it. Schematic from Dennis, K44RUL.
Tom-N4GRF

http://www.kg4rul.info/DavidClarkAdapter.bmp

Dennis: that was the one I was looking for.  Thank you so much. I couldn't recall the back-to-back electrolytics. Very best regards to you, Ann and KBIRD.

73, Tom Gallagher N4GRF (formerly of Charlotte NC).

I have a David Clark H-10-56 headset from the days when I flew aircraft. The headset is an excellent piece of equipment, and I was wondering if any of you Elmer s knew how to connect it to a modern solid state transceiver. I recall that it requires some small voltage DC applied to the microphone circuit to power the mic amplifier module. I'm not sure how much. David Clark is not helpful on explicating their designs.

Most modern transceivers have 8v dc pins on the mic connector (Pin2 on the ICOM 756) which can provide the "phantom" power to the David Clark unit. I'm not certain the voltage requirements of the headset, and I thought of  inserting a small resistor in series with the DC to guard against damaging the amplifier module.  Anybody have a any experience with these headsets?

Kindest regards, and thanks, Tom N4GRF

Many thanks to all of you who replied on the L-4B question. I am grateful for the analysis/advice/encouragement. 73 and kindest personal regards, Tom N4GRF

Carl & Roland: thanks so much for your thoughts here.  I come from the vacuum tube era (licensed in 1966), but I haven't worked tubes since college. The HV on an L-4B is fairly intimidating.

If substituting tubes, one at a time, how much time should elapse before the HV bleeds?  Of course, without the tubes installed (Rolands's suggestion) the bleed should take more time?  I'm hesitant to discharge the HV because I recall doing so is injurious to the filter caps and resistors.

Hello.  I just acquired a Drake L-4B linear amplifier. This morning, I fired it up; heaters glowed beautifully; plate voltage came up to 2,500 v.  However, the grid current meter showed a negative grid current was negative. I could not get any output from the amplifier. I'm wondering if it's an ALC circuit. I used a ICOM 706II to excite the L-4B. Tell me if I need to rig an ALC connection?

Tom N4GRF

Gentlemen:

I feel your (respective) pain. I just retrieved my MFJ-1278 from my equipment museum, to discover that the serial ports are RS-232 multi-pin clunkers, the software was provided on a 5-1/2 " disk, and that the $69.00 software they currently sell is delivered on a 3-1/2 disk. Not much more useful than the 5-1/2 version. Hello? In which decade is MFJ operating?

Over the 45 years since I've been licensed, I have trafficked with all the manufacturers: Lafayette, Allied, Radio Shack--when I was poor and later, ICOM and Yaesu. But I've never dealt with any company like MFJ. I returned a defective Astron power supply three times before it finally was replaced. I rewired a Ameritron linear amplifier to correct several major wiring errors in its factory construction. When I called the MS factory I was stonewalled, but Hams adapt and overcome like the Marines!

The lesson here is clear: the way to send a message is simply to stop buying and advocate for better quality control. Insanity is defined as expecting different results from the same behavior.

Tragically, MFJ purchased the ham division of Cushcraft Antennas--in my four decades, the most responsive plain old helpful group of people in the business. Although it difficult to screw up an antenna company with classic designs, I'll be watching to see how they will destroy this venerable company.

Vote with your feet, and sharpen your pens. After all, we're a fraternity and we should demonstrate fraternal solidarity, comrades!

Tom N4GRF

Gentlemen:

I feel your (respective) pain. I just retrieved my MFJ-1278 from my equipment museum, to discover that the serial ports are RS-232 multi-pin clunkers, the software was provided on a 5-1/2 " disk, and that the $69.00 software they currently sell is delivered on a 3-1/2 disk. Not much more useful than the 5-1/2 version. Hello? In which decade is MFJ operating?

Over the 45 years since I've been licensed, I have trafficked with all the manufacturers: Lafayette, Allied, Radio Shack--when I was poor and later, ICOM and Yaesu. But I've never dealt with any company like MFJ. I returned a defective Astron power supply three times before it finally was replaced. I rewired a Ameritron linear amplifier to correct several major wiring errors in its factory construction. When I called the MS factory I was stonewalled, but Hams adapt and overcome like the Marines!

The lesson here is clear: the way to send a message is simply to stop buying and advocate for better quality control. Insanity is defined as expecting different results from the same behavior.

Tragically, MFJ purchased the ham division of Cushcraft Antennas--in my four decades, the most responsive plain old helpful group of people in the business. Although it difficult to screw up an antenna company with classic designs, I'll be watching to see how they will destroy this venerable company.

Vote with your feet, and sharpen your pens. After all, we're a fraternity and we should demonstrate fraternal solidarity, comrades!

Tom N4GRF

Hey Jim (K9AXN): I found your comments on the Hal SR 400 A very helpful. Did I see a refernce to the Northrop gang? Did NOC buy Hallicrafters? Do you know when?
Many thanks, 73
Tom N4GRF West Palm Beach FLorida