Clansman 321 turf unit

Discussion in 'Weapons, Equipment & Rations' started by jimtylee, May 3, 2011.

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  1. Does anyone know why the turf atu for the Clansman 321 is rated at 25 watts, but the output of the radio is 40 watts am and ssb.......?????????
  2. it's a very inefficient unit and burns up a lot of the power in tuning.
  3. Do not agree with that, are you saying a lot of the rf is going into heating components in the Turf ????
    because 40 watts into the Turf with a bird meter monitoring the rf out flowing into a 50 ohm dummy load or into my doublet is showing 35 watts out............
  4. BuggerAll

    BuggerAll LE Book Reviewer Kit Reviewer

    Everyday a school day. I always thought it was a 'surf'. We had 322's in the Hong Kong Regiment maybe it was the way the guys pronounced it but as I say I thought it was a 'surf' unit - something to do with surfing the airwaves.
  5. There are SURFs and TURFs with Clansman kit BA, so maybe they were saying that.
    Selector unit Radio Frequency and Tuning Unit RF.
  6. It is odd though, i have used the Clansman Turf frequently with my FT-847 RUNNING A 100 WATTS through it and no problem at all....nothing gets even warm in the Turf unit........and looking at the components they are easily rubust enough to cope with quite high power rf.......odd that nobody else has picked up on it in the Ham circles.........
  7. Never said it turns electrical energy to into heat energy.

    Inefficient doesn't necessarily mean that heat is generated as well as whatever is supposed to be. Look at speakers, a great pair of PMC bookshelf speakers will be a much higher efficiency than the ones you buy in Richer Sounds. It doesn't mean the richer sounds ones are going to warm your living room up.

    But essentially the TURF is an inefficient unit. It is fully passive (it does not have a power socket on the front of it) and so the 40W going into it, is both powering the unit, and coming out the other side. Since whatever goes on inside the TURF is powered by the RF output on the radio, a loss of output power is inevitable.

    I am not saying this IS the answer, just one possibility.

    But if you are so content plugging your 100W transmitter into it without problems, why is the answer so important?
  8. the SURF is an object but it does something different.

    the TURF is a TUNING UNIT Radio Frequency and is used for tuning the antenna to suit the frequency being used.

    the SURF is a SELECTOR UNIT Radio Frequency and is apparently used as a filter, to filter out all the frequencies other than the one you're using. If you're operating at 10MHz, the radio will actually emit a little bit of all the other frequencies. Not much, but a little. So, if you were running another HF set next to it at 18MHz, this could be an annoyance due to interference. so the SURF just filters the non-10MHz stuff out. So you will often find SURFs in FFRs with 2x 321s, but not usually in FFRs with only 1x 321.
  9. Can you not help yourself ?
  10. Ask in the Royal Signals section, Roadster280 will have the answer for you.
  11. Its not that the answer is keeping me awake at nights........but its a very strange way of rating a ATU, handles more power but is rated at a lowly 25 watts rating the KW atu at 5 watts.........but as we are all aware it handles 100 easily.
  12. Isnt the purpose of the TURF to fool the transmitter into thinking that it has the full antenna deployed, despite using something more convenient such as the 8' whip. Its more of an antenna matching unit.
  13. You are correct it is a aerial matching unit not a aerial tuning unit, only way to tune a aerial is to shorten or make longer....
    ji g4rek
  14. Is that a TUAAM, then?
  15. I have just got my hands on a Clansman VRC 321 and the 25w Antenna Tuner (TURF) to play with. Unfortunately I do not have any manuals for either although most things seem very straightforward.

    I have figured out how to set the units up and how to connect a coax fed dipole but I am still trying to puzzle out the connections for an end-fed antenna and the counter-poise. There are two knurled knobs on the rear of the TURF, which seem to be for connecting the antenna and the counter-poise but there is nothing to show which connects to which.

    Looking from the front of the set, i.e from “underneath” the connections, they are at the top left and bottom right of the set. I would guess that the top connection is for the antenna and the bottom one is for the counterpoise but is this correct?

    Any advice would be much appreciated.