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eHam Forums / Amplifiers / RE: Second harmonic when operating 160m
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on: February 21, 2013, 12:14:33 PM
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I would not be overly concerned. Maybe "he" has a problem on "his" end. Checking your rig with a spectrum analyzer will tell you what need to know.
If you are running 1500 watts and assuming your second harmonic is "down" 40 dB, you will still be transmitting a 0.15 watt second harmonic. If your second harmonic is "down" 30dB then your second harmonic will be 1.5 watts. Under good conditions 1.5 wats or even 0.15 watt can be heard a very long way.
Dick AD4U
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79
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eHam Forums / Amplifiers / RE: New Amp and 240 volt Line
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on: February 21, 2013, 12:08:45 PM
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What ever you decide:
#14 wire - 15 amp breaker (or smaller) #12 wire - 20 amp breaker (or smaller) #10 wire - 30 amp breaker (or smaller)
Even #14 wire (assuming a reasonable distance from the box to the recepticle) will "run" a 1500 watt output amp. Assuming 50% amp efficiency (including filament current and fan current) you will be drawing no moe than 3000 watts from the AC line
3000 watts / 240 volts = 12.5 amps. Since #14 wire will "handle" 15 amps continuous duty and since SSB and CW are not continuous duty modes, #14 wire will be OK.
If it were me and considering the small additional cost, I would opt for #12 or even #10 wire. Either will have less voltage drop than #14. As your shack "grows" you won't be sorry if you install the larger wire.
Dick AD4U
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81
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eHam Forums / Antennas and Towers and more / RE: help PLEASE uhf vhf jumper
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on: February 19, 2013, 01:17:17 PM
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A good quality barrell connector (Amphenol for example) will have NO practical loss at VHF and acceptable loss at UHF in a typical FM mobile environment. An exception may be weak signal work at UHF, but you don't do that with FM in a vehicle.
Use a good quality barrell connector to extend the length of your coax and enjoy your 8800.
Dick AD4U
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82
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eHam Forums / Boat Anchors / RE: Yaesu FT101 Digital Freq Display
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on: February 19, 2013, 11:45:11 AM
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Maybe I confused my reply above with how to hook up a Heathkit SB-650 digital display to a SB-102 transceiver. I posted from memory. I am not in my shop and I do not have a FT-101E to look at.
I indicated that there were "phono jacks" on the rear of the FT-101E where one connects the FC-601 digital display. There MAY indeed be phono jacks on SOME later FT-101E rigs, however in earlier rigs the signals appear at an 8 or 9 pin round jack on the rear panel.
Either way you will need a cable with the proper "ends" to connect the YC-601 to the FT-101 series of transceivers. In all FT-101 rigs I have seen, the necessary outputs to drive the YC-601 appear at some place on the rear of the rig (phono jacks or 8-9 pin round jack).
All you have to do is to make or find the proper cable to connect the two devices together.
Dick AD4U
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83
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eHam Forums / Mods And Repairs / RE: ICOM IC-251a DC to DC Converter fried
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on: February 19, 2013, 10:49:48 AM
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Ditto on Scott. I sent him two ICOM radios in the past year. One was an R71A HF receiver which is 20? years old. The other one was an R7000 DC-Daylight receiver which is around 30 years old. Both were repaired and updated and perform as new (or better).
Dick AD4U
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84
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eHam Forums / Boat Anchors / RE: Yaesu FT101 Digital Freq Display
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on: February 19, 2013, 10:17:35 AM
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Yaesu made two models of this digital display. The earlier one had red LEDs and the later one had green LEDs. Internally where was little if any difference.
As I remember the display required 3 (?) signals provided by the FT-101 transceiver. The signal jacks are already on the rear panel of most (if not all) of the transceivers. I have a FT-101E in my boatanchor collection that has the required jacks on the rear panel. I am not sure if the earlier transceivers in the FT-101 series had them or not.
In order to connect the digital display all you do is connect the three cables to the corresponding phono jacks on the rear of the transceiver. Small coax with phono plugs on each end will do nicely.
My FT-101E and every one I have worked on for other hams, had a very accurate VFO readout. When you change from USB to LSB you have to recalibrate the main dial via the internal crystal calibrator. Ditto when you change bands. Are you doing this?
Dick AD4U
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eHam Forums / Amplifiers / RE: Metron 1000B on WARC bands?
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on: February 18, 2013, 12:03:44 PM
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I guess that is what I get from repeating what I have read on the internet!
Like the TV ad says, "He is a French model. I met him on the internet. We all know that if it appears on the internet, it must be accurate."
My error and I am glad the MRF454 is still with us.
Dick AD4U
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87
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eHam Forums / Amplifiers / RE: Metron 1000B on WARC bands?
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on: February 18, 2013, 09:04:58 AM
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I only recommended that you be very careful using this amp on the WARC bands because if you blow the finals, you may as well use the amp literally as a boat anchor. The finals are not available at any price.
I had a Metron amp for around 15 years and it never missed a beat. Used properly a Metorn will last forever. Still wish I had it.
Dick AD4U
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eHam Forums / Amplifiers / RE: Metron 1000B on WARC bands?
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on: February 16, 2013, 05:38:11 AM
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If this it the Metron solid state amp made in the 1970's I would be very careful about trying the WARC bands. This amp was made before the WARC bands were available. In this amp there are separate and specific band pass filters for each band (160-10M) and operating it outside of this region MAY burn "something" up.
I hope somebody else can give you better info.
Dick AD4U
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eHam Forums / Mobile Ham / RE: HF & Hybrids?
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on: February 13, 2013, 08:01:27 AM
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I have never owned a hybrid so take what I am saying accordingly.
Most every hybrid battery is around 300V to operate the motor. The 300V produced by the battery must be reduced to 13.8V (nominaly) to operate certain accessories that come with the vehicle and outboard accessories installed by the owner.
What you need to determine is how much extra 13.8V capacity the vehicle provides and whether or not it is enough to operate a typical HF rig.
Dick AD4U
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90
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eHam Forums / Amplifiers / RE: Ameritron AL 572
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on: February 08, 2013, 10:12:53 AM
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Oil? Not familiar with this amp, but since there is "oil" inside, you may have blown a filter cap. By changing out the tubes and still having the problem, you can eliminate an internal tube short. That is unless both sets of tubes are bad.
Dick AD4U
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