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Operating on the 630 Meter Band by John Langridge KB5NJD

Discussion in 'Amateur Radio News' started by N5HZR, Nov 12, 2018.

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  1. KM1H

    KM1H Ham Member QRZ Page

    What does any of that have to do with my radio question?

    As far as location you have 25+ dB over me using WSPR vs my CW. I wasnt trying to belittle your results either, just thought you would get a kick out of my rather basic CW TX (into a 6AQ5 amp simply since I had all the parts vs going SS. The tower simply means I dont require an amp to radiate 5W and that ERP rule makes all us on 630 equal if we want to build an amp in order to radiate that.
    KA0HCP likes this.
  2. AA5CT

    AA5CT Ham Member QRZ Page

    I thought you wrote "A T top vertical hung off the side of a 180' tower and tied into the elevated radials for a phased pair of 1/4 wave 160M verticals sloping from that tower appears to do the job." which would seem to indicate to a fair-minded individual adequate space (or more) to erect same. Many of us have a lot less land to 'work' with. Frankly, I never expected to have the results I have had on 160 meters the last few years, working the Top Band Hams net on 1900 kHz where net control resides up in Pennsylvania. It was a 'fluke' that brought me to 630 meters, and after the 'fluke' I secured the exp lic with which I could do actual experimentation. You mentioned radio again. Well, I really don't want to be 'flooded' with a lot of follow-up questions that are sure to result from the disclosure ...
  3. W0PV

    W0PV Ham Member QRZ Page

    FYI - I have an old Icom IC-735 that is opened up for general coverage xmit and it seems to put out a few watts down there.

    I only live on a city lot too but this week may see the 160m wires re-attached to the 30 ft high 80m vertical T top hat, and an attempt to wind up some added loading inductance to see how close to resonance on 630m it can get. Wonder if any "spots" can be generated :cool:
  4. KM1H

    KM1H Ham Member QRZ Page

    Good info, thanks.

    Whatever works and the key is what leaves the antenna and not how much was required to do it. With WSPR, etc, that is a huge equalizer anyway and you should be heard well...just try to get some efficiency in the ground system.

    It is hearing the other guy that will be a problem on small lots full of all sorts of RFI.

    Good luck.

  5. K6CLS

    K6CLS Ham Member QRZ Page

    Would be much smarter to use the 735 transverter interface, with a transmitter for the band. The pi network on 735 doesn't do a good job on 474khz.
    KA0HCP likes this.
  6. SV1RUX

    SV1RUX XML Subscriber QRZ Page

    Nice to see this chunk of the Medium Wave band being made available to Amateur Radio users.
    472 - 479 Khz. Until very recently, 1999 - 2000, these frequencies were being used by Coast Stations
    around the world to transmit CW traffic to ships at sea, mainly in coastal waters up to a few hundred
    miles away. For example, 472 Khz was allocated to Kuwait Radio 9KK and 476 Khz to Aden Radio 7OA.
    Any ships communicating with these stations would probably use 468 Khz or 480 Khz, which were
    two of the frequencies allocated to shipping.

    Dave SV1RUX
    DL6BCX, W7UUU and AG5DB like this.
  7. KM1H

    KM1H Ham Member QRZ Page

    Im not sure I understand. Does the 735 transverter output provide full transceive on 630 even if the TX power is in the milliwatt range? There is no filtering at those levels for any band if it follows the Kenwood version.

    If the power is via the power amp section what is the actual input power? Id hate to be running ~ 170w INPUT to the finals to get 5W out:eek:
    Disabling the 160M filter section should then maybe provide an unfiltered 100W on 630. A suitable filter could be fitted internally if there is room or externally; I have never been inside a 735 nor studied the manual.....yet.

  8. K6CLS

    K6CLS Ham Member QRZ Page

    No. That's the transverter's job.
  9. N6ITE

    N6ITE Ham Member QRZ Page

    That's really cool about 630m. I'd love to get something working.

    I'm still working on trying to get something setup on 160. I was thinking stealth weather balloon or a WW1 style kite at night. I really like your loop. Nice work!
  10. K0RGR

    K0RGR Premium Subscriber QRZ Page

    I'm surprised at what I can hear down there with my 50 foot wire and a 9:1 balun. I have heard quite a few on WSPR, including stations in Tennessee and Texas. If we can do it on WSPR, FT8 or JT9 should work fine, too.

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