This is only needed to illuminate the meter faces. The 2.5 mm side goes to the meter and the 2.1 mm side goes to the IC-7800. Connect the provided12V DC input jack to the Power jack on the back of the IC-7800. If you prefer to be anonymous write it in the message. Connect the DM-7800’s cable to the Meter jack on the back of the IC-7800. If the message is relate to an article, the article can be selected next to each message.Ĭlick here to write a new message or comment for IC-7800 Note that the message is not related to any article.Ĭlick here to see the article list for IC-7800.ĭo you have any tricks, modifications or constructions for homebrewed equipment that are not on mods.dk, please send the information to mods.dk. This forum message list include all message for that is related to IC-7800, this include message that also is related to articles.
Luckily there is a solution!Īcom has a simple external ALC mod solutions which 100% resolves the problem entirely (simple pot circuit to provide voltage via a 9v battery to the IC-7300 ALC jack) and you can completely control overshoot when driving an external amplifier which has no built in ALC control (such as Acom1000/1010 etc).Note that page can take a while to load, if there are many modifications. With this mod, even at the 10w power setting will spike at 100w for a few milliseconds. The IC-7300 has a horrible overshoot problem out of the box, and this problem is very apparent with certain amplifiers like the SPE, OM and Acom (overdrive warnings and PEP spikes, especially on SSB).
I've also increased output power via the service menu (just 20-40w more) with TX power hex code FF provides 120-140W PEP depending on band (it offers a bit of an edge when on mobile or field day operations)
I've done this mod and the results are *FANTASTIC*, average power is way up (and this is more important than PEP), and my sig reports have dramatically improved. Icom won't provide a schematic because they expect you to buy the entire board as an FRU. It is a 3rd party power supply board made by Futaba part FP2346C.
The lines are On the IC-756 pro II Service Manual appears that this connector is provided to be. This time we need to add the ALC slowdown capacitor here : Hello all, I have an IC-7800 and the internal power supply has failed. Icom IC-756 PROII Ham Radio Amateur Radio Dust Cover. Test proved that 3,3uF works well and could be optimal solution, but 4,7uF will be good as well. The bigger capacitance, the slower ALC rise time. We need to prepare tantallum capacitor, magnifying glasses, and a value of 2,2-4,7uF /16V will do the job for us. So if You are notĮxperienced in SMD soldering or using soldering iron at very FRAGILEĮnviroment - do not try to perform the operation! I will be not responsible for any damage You can make doing the MOD. This listing is for an Icom 7800 brochureLots of valuable info inside if you’re looking to buy one of these transceivers second hand. : Any mistake can cause serious damage to your radio. Seller: frr24 (1,697) 99.7, Location: Caledonia, Ohio, Ships to: Worldwide, Item: 265005350996 ICOM IC-7800 HF/50MHz TRANSCEIVER BROCHURE. Take note that MIC gain and PROC settings remains LOW comparing to this what we can find on various websites concerning low power on SSB, and we are still within 75% of ALC scale! As You probably seen on the video posted in December HERE difference in average SSB power is HUGE at first sight.
And it's not the matter of MIC gain setting nor PROC value. Likewise as in IC-7100 low average SSB power ( but not only SSB - i.e FSK441 and JT6M ) it's the problem of too sharp ALC limiting making the ALC loop acting too fast to let the signal envelope to rise enough. Here's a solution - SSB average power (or "talk average power" ) increase MOD, born after hours spent on examining schematic diagrams, comparing circuit details and ham radio cooperation. So what about their other radios, i.e 746, 756 or any PRO series? Are they piece of *&**(^&^ and should not be used? Kind of bullshit IMO.Īt this point I need to pass my sincere KUDOS to Marios SV0CL for his priceless hints, discussion and help. Quite dissapointing serious factory fooling their users saying that screwed ALC unit is made to comply with the high standards of spectrum purity and A class signal. At a 1kHz offset frequency Receiving frequency: 14.2 MHz Mode: CW, IF BW: 500 Hz Roofing Filter IC-7800 3 kHz, IC-7851 1.
Below is a comparison of the improvement over the IC-7800. Not to mention about saving your throat screaming loud to get more than 30W on SSB. The goal was to dramatically reduce the phase noise that degrades the target signal due to the sum of the entire signal present. If You are owner of 7300 this MOD should make You more happy looking on your small Icom 7300, NEVER connect the transceiver to an AC outlet or to a DC power supply that uses more than 16 V.