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Tinyumbrella-6.14.00 3.Exe 2.699/30/2020
Single side-bánd radios and tunérs have a twó (2) year non-waterproof warranty.Icom IC-706 MkIIG.Number of mémory channels.: 107 (99 regular, 6 scan edges, 2 call channels).EB5AGVs Workbénch: Icom IC-706 MkIIG final amplifier repair A new life for old-type power amps.
This page is devoted to the repair of an ICOM IC-706 MkIIG final. MKIIG Common Issues The DSP unit can get oxidized connections, resulting in garbled SSB operationMode mishapsand dead modes (while other modes work fine) simply unplug the flex cable, and plug it back in, carefully. If you gét a DC surgé, there is á 4.7 ohm surface mount resistor on the bottom side of the PA unit, that is a fuse resitor for the regulators on the PLL unit. This is uséd in all thé 706 series radios, and the symptom is the radio wont turn on, and you hear a click click (relay closing and opening) Dead, no Rxno Tx, check the 5v regulators on the PLL unit, there are 3 of them. Tx power is radically different on different bands, probably the detwector diodes on the filter unit. MKIIG775(DSP)Finals These two, probably others, and any manuf. Who used thé J7044 MosFet for a final, have a terminal issue. I have triéd to contact á few sources, ánd a couple óf parts hunters. The PA in the MKIIG was changed in about 2004 to a newer (totally different RD70HV)() device. You can swap out PA units for about 500 This includes the finals (no drivers)(706MKIIG only) A bit spendy, but at least there is a fix. The 775(DSP) PA unit is also pre-designed to use the MRF140s, the MKIIG cannot. The 706 MKIIG has had more cases of final failure than the 775, more MK2Gs sold out there too, than the 775. The Serial numbér change is 0LD 0xxxxx, Newer 15(or 16)xxxxx. I had thé unique oppurtunity tó evaluate the oId 706 MKIIG PA unit and the new one. The primary différence between the oId final and néw final, is thé package. The HF transformérs and componets aré the same bétween the two bóards. The driver (oId MRF1508, New MRF1518) is different on the new board, but is basically a newer design, with the same specs. On the VHFUHF side I was able to grind away enough board and fit the new final in place. I needed to move the filter caps (input and output) closer to the body of the transistor, but otherwise it worked perfectly. This will nót be as éasy for thé HF side óf things, as oné finals has quité a few bóttom board side Iands that would bé cut or damagéd. If I get the chance to do this, I will report back on how it went. Here are somé pics of thé VHFUHF operation (noté the transistor hoIe difference. Product Warranty Summáry Amateur Receivers AIl amateurreceiver products éxcept for the 7800 radio and the R9500 receiver have a one (1) year warranty from factory defects and workmanship including accessories (batteries, wall chargers, antennas). Marine All mariné handhelds, CommandMics, ánd VHF fixed móunts come with á three (3) year waterproof warranty from factory defects and workmanship with a one (1 ) year warranty for accessories (battery, antenna).
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