| Author |
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Snapperhead
| | Posted on Saturday, November 01, 2003 - 9:16 pm: | 
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Hey, does anybody know what pot controls the led freq counter......It's off about 1kc.......Any help would be appreciated......Thanks |
Ss8541
| | Posted on Saturday, November 01, 2003 - 11:54 pm: |
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-FIRST- are you sure that the freq counter is off, or is it the radio itself? if you are sure that it is the freq counter, then the control is the only one on the freq counter board. the time base in most of these freq counters is 4mhz. if you have a 'sniffer' probe for an external freq counter or access to a service monitor, it is best to '0' the freq of the 4mhz xtal. if not then you will have to 'eyeball' it. |
Snapperhead
| | Posted on Sunday, November 02, 2003 - 9:05 am: |
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Well, Put it this way.......When radio is warmed up. Coarse clarifier is at about 10 oclock and fine is about 1 oclock to get on frequency....It's my friends radio across town.....I use my Kenwoodwood to line him in......When he was able to TX on freq as well as RX fine.....The freq counter was off.....For example.....27.387 is what it was reading after he was on freq....I thought there was some kind of adjustment variable pot to fine tune the counter.........Thanks Ss8541 for advice........73's |
Ss8541
| | Posted on Sunday, November 02, 2003 - 12:29 pm: |
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ok, i can tell from what you posted here that the vco offset oscillator(xtal) and/or the carrier offset oscillator(xtal) are off. by changing the readout of the freq counter, you are only going to hide the problem, and complicate the problem if he tries to 'slide'(with coarse clarifier) to other freqs.
the freq counter could be off too, but the radio itself is definitely off freq because you have to shift the rit so far.
you need to have the radio freqs aligned, and this will fix your problem. if you/he have no one locally to do this properly, then i'm sure that tech307 can work you in. |
Snapperhead
| | Posted on Sunday, November 02, 2003 - 2:24 pm: |
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Well, Radio was bought from you guys.......I'll talk to him and see what he says.........Thanks again |
Ss8541
| | Posted on Sunday, November 02, 2003 - 3:52 pm: |
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Snapperhead, when you said 'bought from you guys' i hope you understand that i am not a part of the copper team. i'm just one of the outsider techs who comes here to help. if you -did- think that i was part of copper, then thanks for the compliment.
if you didn't think that, then forget this post, i just wanted to make that clear before someone at copper/another forum member says that i am passing myself off as a copper tech. |
Forummaster
| | Posted on Sunday, November 02, 2003 - 5:33 pm: |
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We think very highly of SS8541 here at Copper and his technical knowledge is well respected and appreciated on the forum. |
Bruce
| | Posted on Sunday, November 02, 2003 - 7:28 pm: |
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Hummmmmm 8541 Interesting you cant win ... it's no diffrent for me if the officer dosnt hear what he wants ..... your a sharp tech you know how many 5 watt bulbs in the grand cannon are out there..... and bad information they pass along. |
Scrapiron63
| | Posted on Monday, November 03, 2003 - 11:10 am: |
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This might be a 5 watt bulb in the grand cannon, but before I started making any adjustments to the voyager, I would check it on a good freq counter. Here's one reason, the CB/export type radios have the 1 kc shift for sideband, that means if the Voyager freq display is showing 27.385, he is actually transmitting on 27.384 in the LSB mode. If my memory is not completly gone, and sometimes it is, I believe some of the HF rigs don't have the sideband shift. If you have them reading 27.385 LSB mode, thats where your transmitting and receiving. If your kenwood is like that, he would have to read up about 27.386 for you to receive him on 27.385.
Just a thought. scrapiron |
Ca346
| | Posted on Monday, November 03, 2003 - 6:49 pm: |
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Scrapiron!!!
The LIGHT BULB just went ON at MY house. Now I understand why my ICOM sometimes (most times) is receiving sooo many off frequency transmission at 27.384 LSB. But actually more received at 27.3845Mhz.
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Scrapiron63
| | Posted on Monday, November 03, 2003 - 8:36 pm: |
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Hey Ca346, maybe I got lucky and lit up something, ha. Some of the radios do shift 1.5 kc's, I believe all the older ones did. Use to hear a lot of "frequency" arguments involving guys with HF rigs talking to ones that were running CB type radios. That is a mess on 27.385 most of the time. |
Ss8541
| | Posted on Tuesday, November 04, 2003 - 12:19 am: |
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scapiron,
you have the right reasoning here, but what you came up with isn't exactly right. he has two rits/clariifiers here. a fine and a course. one swings 1-1.5khz and the other 5khz or so. the freq counter in this radio is a true freq counter. as long as it is aligned correctly it will show the true frequency that he is on for tx and rx(the display will change freqs when the ptt is pressed if there is a difference between rx and tx). there will be no offset. this all depends on if the carrier oscillator offsets are tuned correctly also. with everthing set right, if the display is showing 27.385 in tx then he is txing on 27.385 in -all- modes.
if both clarifiers were straight up and the display was off, but yet the radio txed and rxed on freq, then it would be the freq counter that was off. since he is having to shift the clarifiers, to be on freq (regardless of what freq counter shows) then this means that the radio itself is out of alignment.
in any event, there is no 1kc offset for ssb in export radios. that is unless you are calling using the clarifier at any place besides straight up the shift. even then, the shift will vary depending on how far away the clarifier is from straight up. |
Scrapiron63
| | Posted on Tuesday, November 04, 2003 - 10:57 am: |
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Thanks for the explanation SS8541. I know the Saturns and other Galaxys will show any difference in TX and RX on their frequency counters, at least on AM, don't remember trying them on sideband, but will check my 88. I had not checked an export lately to see if there was a sideband offset, but I just tried my ranger 2950. With it showing dead center on my external freq counter on AM, ie, 27.3850. When I shifted to LSB and injected an audio tone, the freq reading was down 1.5 kc's, 27.3835, then for USB, it shifted up about the same. So I wonder what I am reading here. Or maybe this radio just happened to be set like that, I have a couple more will check later. thanks, scrapiron |
Ss8541
| | Posted on Tuesday, November 04, 2003 - 7:31 pm: |
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scrapiron,
if your output is 1.5kc low in lsb when you add a tone at the mic jack, then that means you were putting in a 1.5kc tone. a 1.5kc tone in usb would be 27.3865, or 1.5kc higher than 27.385(both mean the same thing).
that is how -ALL- ssb radios work, ham, military, cb, whatever.
if this was in mode then you would have had frequencies at 28.385(carrier) 27.3835(lsb) and 27.3865(usb). this would have given your external freq counter hell and it would have given you some crazy readings. since you were using lsb, the carrier and upper sideband was removed leaving only the lower sideband.
i know this does not help much. i would have to go into detail of how the rxing radio breaks this down to demodulate it. the main thing to remember for ssb is that the audio input signal determines the tx offset and nothing else(under perfect conditions) |
Scrapiron63
| | Posted on Tuesday, November 04, 2003 - 11:31 pm: |
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SS8541, yes that did help, good job of explaining. I have noticed by varying the tone the freq would change several tenths. Some women's voices are hard to tune on sideband, I guess because of the high to low range of their voices. This is something i've wondered about for a long time. thanks, scrapiron |
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