Connection counter frecuency on Atlas 210X help
I need help to connect a frequency counter to the rear external oscillator of Atlas 210X transceiver
I have 2 wires from frequency counter to connect to pins of external oscillator but I dont know what pins should be connected and also whether to keep the pins bridged 2 with 3 and 5 with 6
I will appreciate any help
Thanks and regards
Hi Marquin, sorry to get to this so late but I just now noticed your request. Usually someone answers in a very short time. So if you do happen to come by this posting again maybe I can offer a bit of help.
The VFO for the 210X jumps frequency for each band it covers. The newer method would use a heterodyne mixing scheme with the VFO at a fixed frequency span (usually from 5-5.5Mhz). Such a scheme makes it easier to put a frequency counter on it and use the displayed frequency digits of 0.0-500.0 and ignore the upper digit. In these cases the band switch position will set the Mhz digits to the proper band ie, 3 for the 80 meter band 7 for the 40 meter band and so on. This is very effective provided the heterodyne crystals and the carrier crystals are exactly on frequency. Usually they're not. But it was considered close enough at that time. Today folks are more picky and want the frequency to be correct. This requires a counter that can take in the different oscillator frequencies and mix them for the proper readout.
The frequencies the 210X works at are an IF of 5520Khz and various VFO frequencies to get to the proper band. This is a list of the frequencies the 210X uses; VFO FREQUENCY CHART, MODEL 210x I.F. at 5520 kHz
80/75 METERS 3500- 4000 VFO FREQ 9020- 9520
40 METERS 7000- 7500 VFO FREQ 12520- 13020
20 METERS 14000- 14500 VFO FREQ 8480- 8980
15 METERS 21000-21500 VFO FREQ 15480- 15980
10 METERS 28400 - 29400 VFO FREQ 22880 - 23880
So you can see that most of the time the VFO adds to the IF frequency to get the proper band coverage and on 80/75 and 40 meters the VFO is subtracted to obtain the operating frequency. This is a problem that a straight in frequency counter cannot resolve into a accurate frequency for display. There is an answer though. You would need to get one of the newer counters that can do the things necessary to display the proper frequency. These are inexpensive and readily available from AADE. They are at; http://www.aade.com/dfd1atlas.htm.
You do not remove any wires or jumpers to add a frequency counter to the 210X.
Hope this helps even if it is late.
Last edited by KO6WB; 07-08-2012 at 06:41 AM.