Re: [AMRadio] NC-183D Alignment questions help
John. Lot of interesting stuff there. Well, it is always ABOVE the lower frequency that doesn't track. That is to say: I will use the local oscillator compression trimmer and set to the up frequency i.e. 5 mhz and then go down to the lower frequency i.e. 1.8 mhz for that particular band and in the case of this band (includes 80 meters) I will be approx 250 khz ABOVE the 1.8 mhz frequency it should be at when I run the COMMERCIAL digital readout signal generator. Then you are supposed to move a "loop" around inside the inductance coil form to get on the lower frequency, in this case, 1.8 mhz. But the best I can do in any direction is swing the lower frequency about 25 Khz which is probably about right. Yes, on the alignment regards being careful you are on the "right side" of things. In fact in National's manual they send you down to another band to check to make sure you can hear yourself on the image frequency and tell you if you can't you are on the wrong side of things. As far as the IF's are concerned they are exactly where they need to be on 455 Khz and align right up with the crystal phasing control as they should. So don't believe it has anything to do with the general alignment as it is pretty well described and everything comes out like they say it should. The idea about the additional trimmer on the other end has come to mind but you know the inductor forms would be very hard to get to without a major disassembly project probably to include removing their rather complex main tuning and bandspread capacitor. It is hard for me to believe that the wire wound inductor coils have changed as they are on a firm coil form and in no way distorted. If you followed my first query you will see what I have checked so far. The tuning capacitor is tied to ground in several places running down the base of the capacitor and the chassis actually looks like new (no kidding) and was stored in a house in a den and covered with a sheet for the last twenty five years or so and is in excellent condition all around. I am just running out of ideas and was hoping that someone out there has solved the problem. It's sure over my head at this point. One fellow said he ran into the same thing with his and fiddled with it for several months and finally just sold it. I am not going to do that as I was able to get the tracking pretty close on the 80 and 40 meter bands by using their band alignment instructions and worrying about the tracking from 3.5 to 4 mhz and 7 to 7.3 mhz only. It sure it a beautiful receiver and the first one I saw belonged to "Onie"...W1Z?? and her OM back in 53 or 54 when I belonged to the Framingham Radio Club near Boston and had just got my novice ticket. National always seemed to have some very attractive equipment that worked well. Now, of course, they are sk. 73 Van, K7VS Medford, Oregon - Original Message - From: "John Coleman" <[EMAIL PROTECTED]> To: "'Discussion of AM Radio in the Amateur Service'" Sent: Wednesday, September 26, 2007 3:55 PM Subject: RE: [AMRadio] NC-183D Alignment questions help Is the oscillator freq on the low end too high and needs to be lower or is it to low and needs to be higher. Some one mentioned that the oscillator may be running on the wrong side. You may know this already but I will state it anyway, that the OSC must be running above the RF that you want to receive. OSC = RF + IF. It is some times possible to pull the OSC with the trimmer all the way down to where the OSC = RF - IF. This will work where you set it but it will not track as the manufacture did not design it that way. Assuming that the culprit is ageing coil forms, not incorrect parts or IF misalignment, there could be a number of quick fixes for this type of thing. Padding capacitors can be added in series with the top end of the coils or extra turns could be added to the coil assembly or just placed in series with it. I have beat up some powdered iron and put it into the coil form with glue to lower the frequency. John, WA5BXO -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Van K7VS Sent: Tuesday, September 25, 2007 11:04 PM To: Discussion of AM Radio in the Amateur Service Subject: [AMRadio] NC-183D Alignment questions help I have a pristine NC-183D I picked up a year ago that I am finally getting around to. Have replaced all the electrolytics and sound really good. BUT...I cannot get it to track properly as I follow the alignment instructions in the manual. I can set the top frequency on each band with a small trimmer cap (this is the oscillator coil adjustment) but then according to the instruction manual you adjust the low end of the dial by moving a wire inside an inductor, which does move the lower frequency but not nearly enough to get to the frequency they say you
Re: [AMRadio] NC-183D Alignment questions help
- Original Message - From: "John Coleman" <[EMAIL PROTECTED]> To: "'Discussion of AM Radio in the Amateur Service'" Sent: Wednesday, September 26, 2007 3:55 PM Subject: RE: [AMRadio] NC-183D Alignment questions help Is the oscillator freq on the low end too high and needs to be lower or is it to low and needs to be higher. Some one mentioned that the oscillator may be running on the wrong side. You may know this already but I will state it anyway, that the OSC must be running above the RF that you want to receive. OSC = RF + IF. It is some times possible to pull the OSC with the trimmer all the way down to where the OSC = RF - IF. This will work where you set it but it will not track as the manufacture did not design it that way. Assuming that the culprit is ageing coil forms, not incorrect parts or IF misalignment, there could be a number of quick fixes for this type of thing. Padding capacitors can be added in series with the top end of the coils or extra turns could be added to the coil assembly or just placed in series with it. I have beat up some powdered iron and put it into the coil form with glue to lower the frequency. John, WA5BXO -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Van K7VS Sent: Tuesday, September 25, 2007 11:04 PM To: Discussion of AM Radio in the Amateur Service Subject: [AMRadio] NC-183D Alignment questions help I have a pristine NC-183D I picked up a year ago that I am finally getting around to. Have replaced all the electrolytics and sound really good. BUT...I cannot get it to track properly as I follow the alignment instructions in the manual. I can set the top frequency on each band with a small trimmer cap (this is the oscillator coil adjustment) but then according to the instruction manual you adjust the low end of the dial by moving a wire inside an inductor, which does move the lower frequency but not nearly enough to get to the frequency they say you should see. Has anyone else had that problem during alignment of this receiver, or am I missing something. Have checked the voltages at the first and second converter and they seem fine and have pulled off the mica cap across one of the oscillator coils (1.8 to 5 Mhz) and it checked just fine (supposed to be 1600 pf and reads 1615 pf). And have substituted a different 6BE6 in the first converter and still can't get close to proper or accurate dial tracking. I am 500+ Khz off no matter what I have tried. And thoughts on this one! Thanks. Van, K7VS PS I would like to hear from NC-183D owners that may have experienced this problem or have some thoughts about what I am seeing. tnx __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.488 / Virus Database: 269.13.31/1031 - Release Date: 9/26/2007 12:12 PM __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] NC-183D Alignment questions help
Thats goes to hell in a "ham basket" (sorry). My 183D "gargles" with the BFO on above about 10 MHz, great on AM. 73 & GL K0NG . __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
RE: [AMRadio] NC-183D Alignment questions help
Is the oscillator freq on the low end too high and needs to be lower or is it to low and needs to be higher. Some one mentioned that the oscillator may be running on the wrong side. You may know this already but I will state it anyway, that the OSC must be running above the RF that you want to receive. OSC = RF + IF. It is some times possible to pull the OSC with the trimmer all the way down to where the OSC = RF - IF. This will work where you set it but it will not track as the manufacture did not design it that way. Assuming that the culprit is ageing coil forms, not incorrect parts or IF misalignment, there could be a number of quick fixes for this type of thing. Padding capacitors can be added in series with the top end of the coils or extra turns could be added to the coil assembly or just placed in series with it. I have beat up some powdered iron and put it into the coil form with glue to lower the frequency. John, WA5BXO -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Van K7VS Sent: Tuesday, September 25, 2007 11:04 PM To: Discussion of AM Radio in the Amateur Service Subject: [AMRadio] NC-183D Alignment questions help I have a pristine NC-183D I picked up a year ago that I am finally getting around to. Have replaced all the electrolytics and sound really good. BUT...I cannot get it to track properly as I follow the alignment instructions in the manual. I can set the top frequency on each band with a small trimmer cap (this is the oscillator coil adjustment) but then according to the instruction manual you adjust the low end of the dial by moving a wire inside an inductor, which does move the lower frequency but not nearly enough to get to the frequency they say you should see. Has anyone else had that problem during alignment of this receiver, or am I missing something. Have checked the voltages at the first and second converter and they seem fine and have pulled off the mica cap across one of the oscillator coils (1.8 to 5 Mhz) and it checked just fine (supposed to be 1600 pf and reads 1615 pf). And have substituted a different 6BE6 in the first converter and still can't get close to proper or accurate dial tracking. I am 500+ Khz off no matter what I have tried. And thoughts on this one! Thanks. Van, K7VS PS I would like to hear from NC-183D owners that may have experienced this problem or have some thoughts about what I am seeing. tnx __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] NC-183D Alignment questions help
I sure wish I hadn't had to sell mine!! Ronnie On Wed, 26 Sep 2007 08:50:17 -0500, Jim Wilhite wrote > Van this is a problem with the 183D. I suspect the heat generated > in the closed cabinet has an effect on the inductance of the coils. > They are made of what looks like cardboard dipped in varnish and I > had a couple of the IF transformers that were warped to actually > bind the slugs enough that when I tried to move them the screw > pulled out of the core. > > If the inductance of the oscillator coils has changed then it is a > real problem. Do be sure the trimmer caps are on the correct side > of the curve as Larry mentions. It is difficult, but as you tune > through the peak, on one side the increase will be a bit slower than > the other side of the peak. It will rise slowly then fall rapidly > or the reverse. You want on the slow side and not past it. > > I managed to get mine fairly close by cleaning the contacts of the > tuning capacitor and on a couple of the oscillator coils the wire is > at very maximum inductance, but the dial is close. Good luck and > have fun. Great receiver when is works properly. > > 73 > > Jim/W5JO > > > Hi, > > > > I found on a National RX one time that the oscillator was on the wrong > > side. If it should be high, it was low or visa versa. Be sure that > > is not your case as that will make tracking impossible. > > > > Larry > > W3LW > > > > At 01:03 AM 9/26/2007, > >>I have a pristine NC-183D I picked up a year ago that I am finally > >>getting around to. Have replaced all the electrolytics and sound > >>really good. BUT...I cannot get it to track properly as I follow the > >>alignment instructions in the manual. > > __ > Our Main Website: http://www.amfone.net > AMRadio mailing list > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > To unsubscribe, send an email to [EMAIL PROTECTED] with > the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] NC-183D Alignment questions help
Van I did not make that clear, but I was talking about the main tuning cap and the bandspread variables. If you have all the frequency trimmer capacitors set the same way it is probably as good as it is going to get once you clean and check the variables. Good luck. Jim/W5JO Jim. Are you talking about the small trimmer caps across the coils or are you speaking of the main tuning and bandspread tuning capacitors?? Van (already noted and tried the slow upside on the trimmers with no luck. I can get it to track pretty close by setting the tracking on the ham band I am going to use it on (75 meters). And seems to be fairly close on the bdcst band, not as good as I would like it and then it goes to hell in a handbasket! HI HI. Van __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] NC-183D Alignment questions help
Jim. Are you talking about the small trimmer caps across the coils or are you speaking of the main tuning and bandspread tuning capacitors?? Van (already noted and tried the slow upside on the trimmers with no luck. I can get it to track pretty close by setting the tracking on the ham band I am going to use it on (75 meters). And seems to be fairly close on the bdcst band, not as good as I would like it and then it goes to hell in a handbasket! HI HI. Van - Original Message - From: "Jim Wilhite" <[EMAIL PROTECTED]> To: "Discussion of AM Radio in the Amateur Service" Sent: Wednesday, September 26, 2007 6:50 AM Subject: Re: [AMRadio] NC-183D Alignment questions help Van this is a problem with the 183D. I suspect the heat generated in the closed cabinet has an effect on the inductance of the coils. They are made of what looks like cardboard dipped in varnish and I had a couple of the IF transformers that were warped to actually bind the slugs enough that when I tried to move them the screw pulled out of the core. If the inductance of the oscillator coils has changed then it is a real problem. Do be sure the trimmer caps are on the correct side of the curve as Larry mentions. It is difficult, but as you tune through the peak, on one side the increase will be a bit slower than the other side of the peak. It will rise slowly then fall rapidly or the reverse. You want on the slow side and not past it. I managed to get mine fairly close by cleaning the contacts of the tuning capacitor and on a couple of the oscillator coils the wire is at very maximum inductance, but the dial is close. Good luck and have fun. Great receiver when is works properly. 73 Jim/W5JO Hi, I found on a National RX one time that the oscillator was on the wrong side. If it should be high, it was low or visa versa. Be sure that is not your case as that will make tracking impossible. Larry W3LW At 01:03 AM 9/26/2007, I have a pristine NC-183D I picked up a year ago that I am finally getting around to. Have replaced all the electrolytics and sound really good. BUT...I cannot get it to track properly as I follow the alignment instructions in the manual. __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.488 / Virus Database: 269.13.30/1030 - Release Date: 9/25/2007 8:02 AM __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] NC-183D Alignment questions help
Van this is a problem with the 183D. I suspect the heat generated in the closed cabinet has an effect on the inductance of the coils. They are made of what looks like cardboard dipped in varnish and I had a couple of the IF transformers that were warped to actually bind the slugs enough that when I tried to move them the screw pulled out of the core. If the inductance of the oscillator coils has changed then it is a real problem. Do be sure the trimmer caps are on the correct side of the curve as Larry mentions. It is difficult, but as you tune through the peak, on one side the increase will be a bit slower than the other side of the peak. It will rise slowly then fall rapidly or the reverse. You want on the slow side and not past it. I managed to get mine fairly close by cleaning the contacts of the tuning capacitor and on a couple of the oscillator coils the wire is at very maximum inductance, but the dial is close. Good luck and have fun. Great receiver when is works properly. 73 Jim/W5JO Hi, I found on a National RX one time that the oscillator was on the wrong side. If it should be high, it was low or visa versa. Be sure that is not your case as that will make tracking impossible. Larry W3LW At 01:03 AM 9/26/2007, I have a pristine NC-183D I picked up a year ago that I am finally getting around to. Have replaced all the electrolytics and sound really good. BUT...I cannot get it to track properly as I follow the alignment instructions in the manual. __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] NC-183D Alignment questions help
Good Luck Van I tried the same thing for several months and finally sold the 183D. It is simply an awful design and one of the worst alignment tasks I ever attempted. Cheers Ron W6OM - Original Message - From: "Van K7VS" <[EMAIL PROTECTED]> To: "Discussion of AM Radio in the Amateur Service" Sent: Tuesday, September 25, 2007 10:03 PM Subject: [AMRadio] NC-183D Alignment questions help I have a pristine NC-183D I picked up a year ago that I am finally getting around to. Have replaced all the electrolytics and sound really good. BUT...I cannot get it to track properly as I follow the alignment instructions in the manual. I can set the top frequency on each band with a small trimmer cap (this is the oscillator coil adjustment) but then according to the instruction manual you adjust the low end of the dial by moving a wire inside an inductor, which does move the lower frequency but not nearly enough to get to the frequency they say you should see. Has anyone else had that problem during alignment of this receiver, or am I missing something. Have checked the voltages at the first and second converter and they seem fine and have pulled off the mica cap across one of the oscillator coils (1.8 to 5 Mhz) and it checked just fine (supposed to be 1600 pf and reads 1615 pf). And have substituted a different 6BE6 in the first converter and still can't get close to proper or accurate dial tracking. I am 500+ Khz off no matter what I have tried. And thoughts on this one! Thanks. Van, K7VS PS I would like to hear from NC-183D owners that may have experienced this problem or have some thoughts about what I am seeing. tnx __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] NC-183D Alignment questions help
Hi, I found on a National RX one time that the oscillator was on the wrong side. If it should be high, it was low or visa versa. Be sure that is not your case as that will make tracking impossible. Larry W3LW At 01:03 AM 9/26/2007, you wrote: I have a pristine NC-183D I picked up a year ago that I am finally getting around to. Have replaced all the electrolytics and sound really good. BUT...I cannot get it to track properly as I follow the alignment instructions in the manual. I can set the top frequency on each band with a small trimmer cap (this is the oscillator coil adjustment) but then according to the instruction manual you adjust the low end of the dial by moving a wire inside an inductor, which does move the lower frequency but not nearly enough to get to the frequency they say you should see. Has anyone else had that problem during alignment of this receiver, or am I missing something. Have checked the voltages at the first and second converter and they seem fine and have pulled off the mica cap across one of the oscillator coils (1.8 to 5 Mhz) and it checked just fine (supposed to be 1600 pf and reads 1615 pf). And have substituted a different 6BE6 in the first converter and still can't get close to proper or accurate dial tracking. I am 500+ Khz off no matter what I have tried. And thoughts on this one! Thanks. Van, K7VS PS I would like to hear from NC-183D owners that may have experienced this problem or have some thoughts about what I am seeing. tnx __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
[AMRadio] NC-183D Alignment questions help
I have a pristine NC-183D I picked up a year ago that I am finally getting around to. Have replaced all the electrolytics and sound really good. BUT...I cannot get it to track properly as I follow the alignment instructions in the manual. I can set the top frequency on each band with a small trimmer cap (this is the oscillator coil adjustment) but then according to the instruction manual you adjust the low end of the dial by moving a wire inside an inductor, which does move the lower frequency but not nearly enough to get to the frequency they say you should see. Has anyone else had that problem during alignment of this receiver, or am I missing something. Have checked the voltages at the first and second converter and they seem fine and have pulled off the mica cap across one of the oscillator coils (1.8 to 5 Mhz) and it checked just fine (supposed to be 1600 pf and reads 1615 pf). And have substituted a different 6BE6 in the first converter and still can't get close to proper or accurate dial tracking. I am 500+ Khz off no matter what I have tried. And thoughts on this one! Thanks. Van, K7VS PS I would like to hear from NC-183D owners that may have experienced this problem or have some thoughts about what I am seeing. tnx __ Our Main Website: http://www.amfone.net AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.