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Calibrate a Astatic 600 meter ?..

Discussion in 'CB and Export Equipment and Accessories' started by Oatmeal, Jun 13, 2012.

  1. Oatmeal

    Oatmeal Active Member

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    Is there away to do this yourself, or does it need to be done by a shop tech ?...


     

  2. Wire Weasel

    Wire Weasel Senior Moment

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    Remove the cover. You will several adjustment pots inside. You will of course have to have a 2nd meter on hand whose calibration you trust to have something to re-calibrate it to. The pots may also be in tight spots and you'll need shorty screwdrivers to get to them.

    Check your radio power, mod, swr with 1st meter. Then put the 600 in line and reset the readings to that of the 1st trusted meter. And you will have to do this separately for each of the different power levels too.

    Good luck
     
  3. sp5it

    sp5it Master of puppets

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    Not the best way to do that.
    I prefer to calibrate power reading that way:AI4JI Dummy Load

    For SWR reading calibration you should use 100ohm non inductive resistor array and set SWR=2 with that load.
    Mike
     
    Greg T, psycho and Robb like this.
  4. Wire Weasel

    Wire Weasel Senior Moment

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    I agree but this fellow doesn't exactly sound like he has a lab full of spendy test equipment. This is just something that anybody can do at home and it's good enough for the average CB'er.
     
  5. Robb

    Robb Yup

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    I think the poster that started this tread is asking "Which pot is adjusting what"? Of course, we are dealing with a Astatic 600 meter. Don't know if it is any more or less accurate than a Dosy is. Either one of these isn't a true peak reading meter.

    If there was a schematic available, it should describe what each pot is doing. Or, you can call up the mfr and ask them for some info or a schematic. Don't think that you want to buy a Bird 43 meter - just to calibrate your Astatic 600.

    I agree with sp5it'a method to get any meter tested/corrected for power output accuracy.

    Making a simple 2:1 dummy load can be done by using an old/used PL-239 connector and a 25 cent - 2 watt/100 ohm carbon resistor. Just put it down the PL-239 barrel, solder one lead of the resistor to the PL-239 tip & the other resistor lead to the inside of the barrel of the PL-239, then pack it with vasoline, and then seal it silicone adhesive. Should be enough to handle 4 watts dead key from any CB radio and show a 2:1 SWR reference point for calibration purposes for any meter.
     
    #5 Robb, Jun 13, 2012
    Last edited: Jun 14, 2012
  6. Robert Cook Sr

    Robert Cook Sr New Member

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    I have 2 PDC600, one bought in the 70's and 1 about 10 years ago, I have a MFJ-815D coming. Which of the 3 meters would you say is closer to being correct on everything?
    Both PDC 600 read about same on SWR & power and Modulation
     
  7. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    None of the above? I would say mfj because it is newer. But then it is mfj, so you will probably have to fix it before you use it.......
     
    NightThumper likes this.
  8. NightThumper

    NightThumper Sr. Member

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    This is true...I have the 30 to 300 watt MFJ model and had to take it apart to calibrate against my bird and telepost LP-700 and fix the internal light.
     
    Shadetree Mechanic likes this.
  9. Shockwave

    Shockwave Sr. Member

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    If you're looking for accuracy you'll need something like the Bird, Coaxial Dynamics or the digital Telepost LP-100A. The problem with analog meters is even when calibrated, they struggle to maintain accuracy over the entire scale. The best two analog meters mentioned above, are within 5% and that's only once you're above half scale deflection. On the other hand, is that much accuracy really required in this case? If it is, you'll need a better meter. If not, don't even worry about the difference. If one of the three reads way different than the other two, don't trust that one without confirming their readings.
     
  10. Robert Cook Sr

    Robert Cook Sr New Member

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    I received the MFJ =815D meter, power meter wanted to hang about mid-way power reading then jump up to reading, not long but a second or 2 plus swr was reading about same as pdc600's so I'm sending back, doesn't seem to be any better than my pdc600. By the way PDC600 are no longer made, can't find one anyplace.. I have a MFJ-815B that's no long made was closer than new 815D modal.
     
  11. Robert Cook Sr

    Robert Cook Sr New Member

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    Can anyone tell me which pot is for adjusting Watts in a Astatic 600 meter I need to calibrate another used one that seems to be much higher than others I have for Watts , also which diode is for getting swinge in watts reading. It reads watts just no forward swing like my other PDC 's do plus I read that Astatic had a more sensitive SWR meter than other PDC's can anyone verify that for me??
     
  12. Tokin

    Tokin The Man With No Shoes

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