easy and sucsessful op on LF

Discussion in 'The Low Bands - 630/2200 Meters - VLF' started by WA1MTZ, Aug 12, 2019.

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  1. WA1MTZ

    WA1MTZ Ham Member QRZ Page

    no need to reinvent the wheel, I use a arc-5 rx on 630m, a bc779 on 185 kc and an ATR-13 xmtr with a bc-603 ant tuner. use an rf ammeter! ur ant Z will be abt 2 ohms! If you can find a Nautel
    beacon tx you will have something real nice! has built in audio compression too, solid state PDM
    tx
     
  2. K9STH

    K9STH Platinum Subscriber Volunteer Moderator Platinum Subscriber QRZ Page

    ATR-13?

    I am not familiar with that unit. However, the Collins ART-13 with the LF module will work on the 630-meter band.

    Glen, K9STH
     
  3. WA1MTZ

    WA1MTZ Ham Member QRZ Page

    wow, it should have been labeled ART-13! sri abt that! also, I hope that any newcomers be advised that you need a VERTICAL ant to tx on LF, horizontal, and beverage types are good for rx only. Some of the best antennas are the cage type vertical s 4 wires spaced 10' apart on a wood mast about 30' high, bottom about 8' off the gnd ,all 4 wires connected together, another good antenna is the 'T' top has 2 wires spaced 8' 80-100' long with 2 wires coming down from the centre to ground level and a loading coil-no capacitors used, just inductance. coil should be litz cable or #8 wire, remember the Z is so low that the loss in the coil can be high. a book written in the 1950's by ITT, is avail free download at https://archive.org 500 page communications manual, look under LF antennas. ps, most air beacon stations ran 25-50w with loaded vert 35'
     
  4. K9STH

    K9STH Platinum Subscriber Volunteer Moderator Platinum Subscriber QRZ Page

    MTZ:

    I figured that it was really an ART-13. I have never owned one but have seen a few of the transmitters.

    For receiving, on the 630-meter band, I can choose from a BC-453, BC-348, TS-440SAT, or a receiving converter into my Heath SB-301. Receiving below 210 kHz I use a Rycom 6010. It is an AM / SSB "selective voltmeter" which is actually a VLF receiver. The Rycom has a digital readout and is very sensitive.

    True ground wave propagation is present on the 2-lowest frequency bands and a vertical is absolutely necessary for true ground wave.

    Glen, K9STH
     

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