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Vintage Amateur and Military Radio Amateur/military receivers and transmitters, morse, and any other related vintage comms equipment. |
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2nd Jul 2020, 4:20 pm | #21 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
Posts: 11,577
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Re: PCMA001S No Rx or Tx issues...
Conventionally, the 20.555 crystal is the one which generates the band immediately above 'Hi', i.e, the block commencing at 27.865.
I'm not sure whether that radio uses one crystal per 40-channel band or a combination of fewer crystals and PLL code manipulation via PROMs to generate all of its bands. With the age these radios are now, if a decent one came into my hands I would actually restore it to its original channel / band range, whatever that was. |
2nd Jul 2020, 5:40 pm | #22 | |
Triode
Join Date: Jun 2020
Location: Medway Towns, Kent, UK.
Posts: 26
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Re: PCMA001S No Rx or Tx issues...
Quote:
ok the Nato 2000 has five crystals... Frequency range: Band A: 26.065 to 26.505 MHz Band B: 26.515 to 26.955 MHz Band C: 26.965 to 27.405 MHz (FCC band) Band D: 27Л15 to 27.855 MHz Band E: 27.865 to 28.305 MHz Band F: 28.315 to 28.755 MHz In some models, Band E is called "FM" and contains the UK CB band of 27.60125 MHz to 27.99125 MHz, with no Band F. Band A. Adjust CT-1 for 19.655 MHz Band B. Adjust CT-2 for 19.880 MHz Band C. Adjust CT-3 for 20.105 MHz Band D. Adjust CT-4 for 20.330 MHz Band E. Adjust CT-12 for 20.555 MHz Band E may contain the UK-FM band, in which case crystal is. 20.423 MHz. Some models may contain only 3 crystals of 19.655 MHz (Bands А & В), 20.105 MHz (Bands C & D), and 20.555 MHz (Bands E & F) The Nato 2000 has a unique channel selector from what I understand? This radio is rough, cracked/broken/scratched fascia... missing knobs etc. Definately not one a collector would be interested in... put it that way! I can use the 10m band so would not feel bad about making it more useable for me. |
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2nd Jul 2020, 6:23 pm | #23 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
Posts: 11,577
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Re: PCMA001S No Rx or Tx issues...
Really five crystals? I count six bands there, so there would usually be six loop mixer crystals.
The radio must also have PROM(s) to untangle the 'FCC' order of frequencies from the channel switch into a straight run of ascending 10KHz steps for the UK band - either that or an extra wafer on the channel switch dedicated to outputting 40 ascending PLL codes for the UK band. The handful of Nato 2000s I ever saw all had the UK channels on the last band, but then all the ones I saw were UK examples. There are only two other sets I can think of which also had the UK channels straight out of the box. The Commtron 'Nato CXX' was based on the standard Maxon chassis of the time with a large bank of crystals switched in and out to generate the consecutive frequencies of the UK band. The Stalker 9F from Uniden also came in a UK specific version, on which one band had the UK channels. |
2nd Jul 2020, 6:44 pm | #24 | ||||
Triode
Join Date: Jun 2020
Location: Medway Towns, Kent, UK.
Posts: 26
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Re: PCMA001S No Rx or Tx issues...
Quote:
The A to F was to show what this board/chassis can cover... The Nato 2000 is... Band A - 19.655 MHz ~ L-Lows Band B - 19.880 MHz ~ Lows Band C - 20.105 MHz ~ Mids Band D - 20.330 MHz ~ Highs Band E - 20.423 MHz ~ UK40 Quote:
Quote:
labelled left to right = FM, A, B, C, D Quote:
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2nd Jul 2020, 11:50 pm | #25 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
Posts: 11,577
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Re: PCMA001S No Rx or Tx issues...
The 'UK' version of the Stalker 9 has a CB/27/81 logo screen printed on the front panel.
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3rd Jul 2020, 6:19 pm | #26 | |
Triode
Join Date: Jun 2020
Location: Medway Towns, Kent, UK.
Posts: 26
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Re: PCMA001S No Rx or Tx issues...
Quote:
Going back to the relay/capacitor mod... I'm wondering if it is something to do with the USB/LSB modulation? From reading it seems these and the earlier boards suffered distorted/gritty sounding modulation? |
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