More Amplifiers

First of the new amps is this 1.8mhz-30mhz 500w HF amp. It has 4 ea 2879 transistors and good for about 65-70w input. Output varies with the frequency and it gets a little more than 500W out on 80m and a little less on 10m. It is RF switched so not much use for anything other than voice. No externat PTT. It has quite good protection built in for overdrive, over heat and hi SWR. Originally it came with just a fan on the inside but where could the air go? Just a few slots in the back to exhaust…not enough air flow and no where to go. We asked the manufacturer to place a fan on top which he has done and now it stays a lot cooler. Quite a bit of heat sink for an amp of this type but without the added fan, once it gets hot it stays hot. Not much to say about it…pretty tough hi input power, low input SWR, solid state no tune amp that can work anywhere. Best we have found for the price so far. Order from www.Yeticomnz.com for your next portable outing.

 

Another AMp this time 2m. Tested to 330W FM. Nice and tidy. Lots of power on 2m for those that need to be heard. Nicely made.

 

From RM we have a 100w amp for UHF CB. Works up to 477mhz but output only 85-90w. Not bad for 5w input. Like all UHF amps a little expensive but it delivers the goods. Another keeper for the mobile or working the repeaters from far away.

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2 Responses to More Amplifiers

  1. blob says:

    It appears that the HF amplifer does not have low pass filters for each amateur band.At claimed maximum output when used on 1.8MHz or 3.5MHz what levels are the harmonics at?At claimed maximum output how much splatter does it produce? (ideally spectrum analyser view of a two tone test).Are the harmonics strong enough to cause harmfull interference to people a few miles away using higher band?On a croweded band like 7MHz where someone else may be trying to use the bit of the bandright next to you will your splatter affect their reception?Does it meet the requirements of your local radio regulator for how clean the signal is?I suspect the answers will be something like "about 20 watts in total of harmful interference to other bands", "about 4 s-points down in the 3Khz slot up or down", "yes", "yes", and "nowhere near".

    • dd182003 says:

      sorry about the delay as I have just started reading the responses to the blog.
      You are quite correct in your observation that the amplifier has no filtering on the output at all.
      At the claimed maximum output I am sure there must be splatter. As long as driven normally at 40-50 watts it shouldn’t be too bad.
      In a mobile situation I would expect most users to be running some sort of tuned antenna system which should negate(filter) the 3rd order harmonics.
      But it is what it is….a broadband solid state amp with no filtering

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