Recent content by kd4e

3-amps-for-1 & Worth-More I tried to get one from him years ago as well and could not. I have three 1200w ss amps (they use eight MRF422's each) from a Danish Marine company called Skanti. One has inadequate 80, 40, 20m filters & they all really needs something like the Worth-More Chebyshev...

There is an interesting comparison chart here: NAPRS APRS Radio comparison chart It would be helpful if it were updated to show the VX-8GR rather than the older models.

Does the Yaesu keep the same resources active or do they go into a sleep mode to save power? Perhaps the Kenwood could be hacked to provide the same power-saving effect?

I am looking at these devices for an APRS handheld and primitive text messaging, e.g. Skywarn reports and casual texts. I will see if I can find your other posts re. these HT's. Have you controlled for active-processes between the Kenwood and Yaesu as may impact battery performance? In the...

ACCORDING TO UNIVERSAL THIS COVERAGE IS ALREADY THERE FOR RX, THAT MAY EXPLAIN THE MISSING DIODE Frequency Coverage: VHF: Tx: 144-148 MHz Rx: 136-174 MHz (guaranteed 144 - 148 MHz only) UHF: Tx: 420-450 MHz (guaranteed 440 - 450 MHz only) Rx: 400-479 MHz (guaranteed 440 - 450 MHz...

The 30a MFJ-4416 according to the one eham review is defective and they are trying to sort out a fix. It is currently priced at $139. per the eham site: http://www.eham.net/reviews/detail/7504 N8XJK claims that MFJ "stole" his old design but he has a new and improved one that is 40A CCS $225...

Pictures sent, private mail. Thanks! doc

Our Sunday fellowship begins soon so I will have to take and post pictures later. I have the model with the eight MRF-455's. I have the fan kit but not the remote. It is in good condition, not abused. We tested it at a friend's house (I don't have enough current yet to power it at 13.8vdc...

What's a Messenger 4V Worth? I may have to sell mine to help pay for a replacement computer. If I have to do this what should I ask? Mine has the MRF-455's, is in decent shape, and works fine. Thanks! doc KD4E

I am guessing that the "high speed 75 Amp Magnetic Circuit Breaker" is sensing current surges and is tripping - an alternative to a superior but more complex VSWR sensing circuit. WDYT? I will also need to do something about band-switch filters.

I just read this description about the Metron MA-1000 amp: "A high speed 75 Amp Magnetic Circuit Breaker protects against short circuits, overdrive, and mismatched antennas. A protective diode will not allow the amp to operate if the supply polarity is accidentally reversed. A 75 degree...

Sounds like 13.8V is about right then. Have you made any mods to improve the bias circuit that you could share, please? Any other improvements? I presume that some of the combiner-splitter and transformers may need to be replaced in order to improve efficiency - yes? I am hoping for 40-10M...

13.8 minimum, hmmmm, I wonder if that is due to current-handling capacity? (Lower voltage = higher current.) I am wondering as the Motorola Spec Sheet shows 12.5V as the test voltage. Right now I am planning a US Battery US 12V XC 155aH (75A for 77min) with a 25A float charge. Perhaps I...

So even base where a higher operating voltage would be convenient 13.8 is optimum? OK re. the extra battery (perhaps an Optima or Deka deep-cycle? OK re. the 120A alternator - is that commonly available or what I have heard referred to as an "ambulance alternator"?

What is the best operating voltage for a Messenger M4V? Mine has eight MRF-455's in the output instead of the 1446's. I have seen references from 12V to 17V, 17V seems too high. I am not as concerned with absolute maximum output as I am to protect the amp and to use the highest safe voltage...