Re: [AMRadio] AM modulation
Jose: Look here: http://www.qsl.net/wa5bxo/amtech.html 73 Jim W5JO - Original Message - From: "Jose HF Silva" <[EMAIL PROTECTED]> To: Sent: Monday, January 09, 2006 8:57 PM Subject: [AMRadio] AM modulation Hi, Where can we find that page? 73 de Jose - CT1AXG Original message: ... ... Read the John/Don/Bacon page about asymetrical audio. It's written well, it's illustrated well, and completely discusses high-level, plate modulated audio and how much you -really- need. "Operating your AM Rig with out an oscilloscope, is like driving your car at night without headlights." (-K4KYV/Don Chester - AM Press Exchange) --- 73 = Best Regards, -Geoff/W5OMR __ Yahoo! DSL - Something to write home about. Just $16.99/mo. or less. dsl.yahoo.com __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
[AMRadio] AM modulation
Hi, Where can we find that page? 73 de Jose - CT1AXG Original message: ... ... Read the John/Don/Bacon page about asymetrical audio. It's written well, it's illustrated well, and completely discusses high-level, plate modulated audio and how much you -really- need. "Operating your AM Rig with out an oscilloscope, is like driving your car at night without headlights." (-K4KYV/Don Chester - AM Press Exchange) --- 73 = Best Regards, -Geoff/W5OMR __ Yahoo! DSL Something to write home about. Just $16.99/mo. or less. dsl.yahoo.com
Re: [AMRadio] Modulator iron & ideas needed
On 8 Jan 2006 at 23:47, RJ Mattson wrote: > Hi Mark, > Are you in range of the K1JCL 6m 50.4 AM repeater in CT? > I tried 50.4 here from the Catskills but never heard anything with my 6m > Clegg. > I have a 6m WRL Comet 7C-6A Techceiver you can try to check for local > activity before you expend to much time and money. > 73 > bob...w2ami x wn2ami 1962 Local activity? What about SKIP on 50.4? It happens! Plenty of stations on these days nationwide.
Re: [AMRadio] Yaesu FT-101EX on AM
Yes the Yaesu FT101 series work very well on AM. Wait until you GET the radio before you decide which crystals you need. Someone may have already added them. You can order these in HC50 holders from JAN Crystals, ICM etc. but they will NOT be cheap! It's easy to get the formula from the manual for these radios. You should be able to download it and get the information off the web too. Sources for crystals are listed here: http://www.af4k.com/mega/xtals.htm AND HERE: http://www.af4k.com/Boatanchors_Directory/Crystals.htm On 9 Jan 2006 at 15:05, [EMAIL PROTECTED] wrote: > > Greetings! > > I might be getting an FT-101EX and I have heard they do > well on AM, if properly operated. > > This one is the > EX model and of course needs the AM filter, but also needs crystals for 160 > and two segments of 10 meters. Since I would most likely use it on 10, I wuz > wonderin' if any of you know where I might get the required crystalsAND > what's the frequency of the crystal(s)? I have read the manual and there > doesn't seem to be any information about crystal frequency in there, or maybe > I don't have a complete manual. > > Any of y'all usin' one for AM? > > Thanks es > > 73 de Dan -- WAØJRD .. > > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb >
Re: [AMRadio] Millen High Voltage Connectors
That's what cable markers are for! Healthfully yours, DON W4BWS - Original Message - From: "Brett gazdzinski" <> To: "'Discussion of AM Radio'" Sent: Monday, January 09, 2006 5:55 PM Subject: RE: [AMRadio] Millen High Voltage Connectors > What is wrong with ceramic feedthroughs? > > I don't think I like the idea of using RF connectors for high voltage, > what happens if you or someone else mix it up with RF antenna or output > stuff? > > Brett > N2DTS > > -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Ed Swynar > Sent: Monday, January 09, 2006 4:01 PM > To: Discussion of AM Radio; [EMAIL PROTECTED] > Subject: Re: [AMRadio] Millen High Voltage Connectors > > Hi Dave, > > I solved the problem of HV B+ arc-overs here by exclusively using NOTHING > but good-quality SO-239 coax receptacles, & RG-8 coax lines for the B+ > leads, terminated in good-quality PL-259's... > > Works like the proverbial charm --- have yet to encounter ANY arc-over > failures since adopting this approach universally at my station in the late > 70's... > > ~73~ Eddy VE3CUI - VE3XZ > > PS: Emphasis on the words "...good-quality" --- NONE OF THAT CHINESE JUNK > here!!! > > > > > > > - Original Message - > From: "david knepper" <[EMAIL PROTECTED]> > To: ; <[EMAIL PROTECTED]> > Sent: Monday, January 09, 2006 3:50 PM > Subject: [AMRadio] Millen High Voltage Connectors > > > > My homebrew transmitter, designed by Stan, W3TGR now a silent key, is > > going through exhaustive and often frustrating testing. Stan used lots of > > shielded wire - you know the Belden stuff that is deteriorating over time > > with brittle insulation on the wire. I had to replace several leads > because > > the center conductor was shorting to ground when the insulation became > > brittle. So it goes ... > > > > Today, I thought that I had finally debugged the unit - pair of 813's > > modulated by 805's - but I heard the troubling sound of high voltage to > > ground. Measuring the Millen connectors to ground revealed a short. Here > > the Millen connectors on the modulator were arcing to ground on the > > secondary side of the modulation transformer running from the high voltage > > through the secondary winding to the PA amplifier. I am using those > light > > tan units that are supposed to be better than the red connectors. Stan > used > > these connectors on the PA amplifier, the modulator deck, and the high > > voltage power supply. > > > > I suppose that under modulation that the peaks exceeded the voltage rating > > of the Millen connectors. Once before many years ago, I had the same > > problem. However, these connectors are often used in homebrew > construction > > projects as described in the ARRL handbook. > > > > Any ideas out there other than to go with ceramic feedthrough insulators. > > > > Perhaps, it is because of their age and the insulation is breaking down. > > Who knows! > > > > Thanks > > > > Dave, W3ST > > Publisher of the Collins Journal > > Secretary to the Collins Radio Association > > www.collinsra.com - the CRA Website > > Now with PayPal > > CRA Nets: 3805 Khz every Monday at 8 PM EST > > and 14255 every Saturday at 12 Noon EST > > > > > > __ > > AMRadio mailing list > > Home: http://mailman.qth.net/mailman/listinfo/amradio > > Help: http://mailman.qth.net/mmfaq.html > > Post: mailto:AMRadio@mailman.qth.net > > AMfone Website: http://www.amfone.net > > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > > > > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb >
Re: [AMRadio] Millen High Voltage Connectors
Well stated Brett. Mike(y) W3SLK - Original Message - From: "Brett gazdzinski" <[EMAIL PROTECTED]> To: "'Discussion of AM Radio'" Sent: Monday, January 09, 2006 6:55 PM Subject: RE: [AMRadio] Millen High Voltage Connectors What is wrong with ceramic feedthroughs? I don't think I like the idea of using RF connectors for high voltage, what happens if you or someone else mix it up with RF antenna or output stuff? Brett N2DTS -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Ed Swynar Sent: Monday, January 09, 2006 4:01 PM To: Discussion of AM Radio; [EMAIL PROTECTED] Subject: Re: [AMRadio] Millen High Voltage Connectors Hi Dave, I solved the problem of HV B+ arc-overs here by exclusively using NOTHING but good-quality SO-239 coax receptacles, & RG-8 coax lines for the B+ leads, terminated in good-quality PL-259's... Works like the proverbial charm --- have yet to encounter ANY arc-over failures since adopting this approach universally at my station in the late 70's... ~73~ Eddy VE3CUI - VE3XZ PS: Emphasis on the words "...good-quality" --- NONE OF THAT CHINESE JUNK here!!! - Original Message - From: "david knepper" <[EMAIL PROTECTED]> To: ; <[EMAIL PROTECTED]> Sent: Monday, January 09, 2006 3:50 PM Subject: [AMRadio] Millen High Voltage Connectors > My homebrew transmitter, designed by Stan, W3TGR now a silent key, is > going through exhaustive and often frustrating testing. Stan used lots of > shielded wire - you know the Belden stuff that is deteriorating over time > with brittle insulation on the wire. I had to replace several leads because > the center conductor was shorting to ground when the insulation became > brittle. So it goes ... > > Today, I thought that I had finally debugged the unit - pair of 813's > modulated by 805's - but I heard the troubling sound of high voltage to > ground. Measuring the Millen connectors to ground revealed a short. Here > the Millen connectors on the modulator were arcing to ground on the > secondary side of the modulation transformer running from the high voltage > through the secondary winding to the PA amplifier. I am using those light > tan units that are supposed to be better than the red connectors. Stan used > these connectors on the PA amplifier, the modulator deck, and the high > voltage power supply. > > I suppose that under modulation that the peaks exceeded the voltage rating > of the Millen connectors. Once before many years ago, I had the same > problem. However, these connectors are often used in homebrew construction > projects as described in the ARRL handbook. > > Any ideas out there other than to go with ceramic feedthrough insulators. > > Perhaps, it is because of their age and the insulation is breaking down. > Who knows! > > Thanks > > Dave, W3ST > Publisher of the Collins Journal > Secretary to the Collins Radio Association > www.collinsra.com - the CRA Website > Now with PayPal > CRA Nets: 3805 Khz every Monday at 8 PM EST > and 14255 every Saturday at 12 Noon EST > > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
RE: [AMRadio] Millen High Voltage Connectors
They are fine when the connection is inside an interlock protected cabinet. Not very conveinent for troubleshoting or working on the equipment, but they work fine. If the connector is outside the cabinet then naturally it must not have an exposed terminal. I also agree on the RF connectors for high voltage. Even if it's marked it is too easy for you, or someone else to make a fatal mistake. This is made worse by using coax (a common RF cable). That's just bad design. Spend a few extra bucks and get the proper connector, one that's safe. Life is too short to mess around. 73, Mark W1EOF > -Original Message- > From: Brett gazdzinski [mailto:[EMAIL PROTECTED] > Sent: Monday, January 09, 2006 6:56 PM > To: 'Discussion of AM Radio' > Subject: RE: [AMRadio] Millen High Voltage Connectors > > > What is wrong with ceramic feedthroughs? > > I don't think I like the idea of using RF connectors for high voltage, > what happens if you or someone else mix it up with RF antenna or output > stuff? > > Brett > N2DTS > > -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Ed Swynar > Sent: Monday, January 09, 2006 4:01 PM > To: Discussion of AM Radio; [EMAIL PROTECTED] > Subject: Re: [AMRadio] Millen High Voltage Connectors > > Hi Dave, > > I solved the problem of HV B+ arc-overs here by exclusively using NOTHING > but good-quality SO-239 coax receptacles, & RG-8 coax lines for the B+ > leads, terminated in good-quality PL-259's... > > Works like the proverbial charm --- have yet to encounter ANY arc-over > failures since adopting this approach universally at my station > in the late > 70's... > > ~73~ Eddy VE3CUI - VE3XZ > > PS: Emphasis on the words "...good-quality" --- NONE OF THAT CHINESE JUNK > here!!! > > > > > > > - Original Message - > From: "david knepper" <[EMAIL PROTECTED]> > To: ; <[EMAIL PROTECTED]> > Sent: Monday, January 09, 2006 3:50 PM > Subject: [AMRadio] Millen High Voltage Connectors > > > > My homebrew transmitter, designed by Stan, W3TGR now a silent key, is > > going through exhaustive and often frustrating testing. Stan > used lots of > > shielded wire - you know the Belden stuff that is deteriorating > over time > > with brittle insulation on the wire. I had to replace several leads > because > > the center conductor was shorting to ground when the insulation became > > brittle. So it goes ... > > > > Today, I thought that I had finally debugged the unit - pair of 813's > > modulated by 805's - but I heard the troubling sound of high voltage to > > ground. Measuring the Millen connectors to ground revealed a > short. Here > > the Millen connectors on the modulator were arcing to ground on the > > secondary side of the modulation transformer running from the > high voltage > > through the secondary winding to the PA amplifier. I am using those > light > > tan units that are supposed to be better than the red connectors. Stan > used > > these connectors on the PA amplifier, the modulator deck, and the high > > voltage power supply. > > > > I suppose that under modulation that the peaks exceeded the > voltage rating > > of the Millen connectors. Once before many years ago, I had the same > > problem. However, these connectors are often used in homebrew > construction > > projects as described in the ARRL handbook. > > > > Any ideas out there other than to go with ceramic feedthrough > insulators. > > > > Perhaps, it is because of their age and the insulation is breaking down. > > Who knows! > > > > Thanks > > > > Dave, W3ST > > Publisher of the Collins Journal > > Secretary to the Collins Radio Association > > www.collinsra.com - the CRA Website > > Now with PayPal > > CRA Nets: 3805 Khz every Monday at 8 PM EST > > and 14255 every Saturday at 12 Noon EST > > > > > > __ > > AMRadio mailing list > > Home: http://mailman.qth.net/mailman/listinfo/amradio > > Help: http://mailman.qth.net/mmfaq.html > > Post: mailto:AMRadio@mailman.qth.net > > AMfone Website: http://www.amfone.net > > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > > > > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > > > -- > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.1.371 / Virus Database: 267.14.15/223 - Release Date: 1/6/06 > -- No virus found in this outgoing
RE: [AMRadio] 7285Kc tomorrow/Saturday
I use a scope on the IF output of the receiver, if you don't have one, its easy to add. That way, you can look at your audio, and everyone else's. You also do not need a fast scope, just the IF frequency. The R390 series receivers have a very nice IF output, works when muted The trapezoid pattern is better, but I never actually hooked up a scope to get one. Brett N2DTS -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Bob Macklin Sent: Monday, January 09, 2006 6:13 PM To: Discussion of AM Radio Subject: Re: [AMRadio] 7285Kc tomorrow/Saturday A scope that produces the trapazopid patern is better for monitoring modulation! Bob Macklin K5MYJ Seattle, Wa. - Original Message - From: "John E. Coleman (ARS WA5BXO)" <[EMAIL PROTECTED]> To: "'Discussion of AM Radio'" Sent: Monday, January 09, 2006 7:13 AM Subject: RE: [AMRadio] 7285Kc tomorrow/Saturday I think what Mark is saying is that it it's difficult to tell what percentage modulation you're at when the wave form is not a sine wave and is not synced and this is true. You just have to get as close as you can with out pinching the carrier (not too often anyway). An automatic gain control circuit helps a lot with this. I did with out one for years learning how to talk by watching the scope. But it is a lot nicer and more relaxed when you have one. John -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of W5OMR/Geoff Sent: Monday, January 09, 2006 5:09 AM To: Discussion of AM Radio Subject: Re: [AMRadio] 7285Kc tomorrow/Saturday Mark K3MSB wrote: >Yes. I've tried a scope now and then (I have an old 60 Mhz B&K), but >truthfully I've never been able to really see when the modulation >level is 100% or other. I know what ideal waveforms look like (with >test inputs), but I have a hard time with a typical speech waveform. > I guess if I'm really at 20% that would be fairly easy to discern. >When I used the scope before I was trying to figure out how to tell if >I was say at 70%, 80%, 90% etc, and never felt I could do it >accurately. > Read the John/Don/Bacon page about asymetrical audio. It's written well, it's illustrated well, and completely discusses high-level, plate modulated audio and how much you -really- need. "Operating your AM Rig with out an oscilloscope, is like driving your car at night without headlights." (-K4KYV/Don Chester - AM Press Exchange) --- 73 = Best Regards, -Geoff/W5OMR __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
RE: [AMRadio] Millen High Voltage Connectors
What is wrong with ceramic feedthroughs? I don't think I like the idea of using RF connectors for high voltage, what happens if you or someone else mix it up with RF antenna or output stuff? Brett N2DTS -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Ed Swynar Sent: Monday, January 09, 2006 4:01 PM To: Discussion of AM Radio; [EMAIL PROTECTED] Subject: Re: [AMRadio] Millen High Voltage Connectors Hi Dave, I solved the problem of HV B+ arc-overs here by exclusively using NOTHING but good-quality SO-239 coax receptacles, & RG-8 coax lines for the B+ leads, terminated in good-quality PL-259's... Works like the proverbial charm --- have yet to encounter ANY arc-over failures since adopting this approach universally at my station in the late 70's... ~73~ Eddy VE3CUI - VE3XZ PS: Emphasis on the words "...good-quality" --- NONE OF THAT CHINESE JUNK here!!! - Original Message - From: "david knepper" <[EMAIL PROTECTED]> To: ; <[EMAIL PROTECTED]> Sent: Monday, January 09, 2006 3:50 PM Subject: [AMRadio] Millen High Voltage Connectors > My homebrew transmitter, designed by Stan, W3TGR now a silent key, is > going through exhaustive and often frustrating testing. Stan used lots of > shielded wire - you know the Belden stuff that is deteriorating over time > with brittle insulation on the wire. I had to replace several leads because > the center conductor was shorting to ground when the insulation became > brittle. So it goes ... > > Today, I thought that I had finally debugged the unit - pair of 813's > modulated by 805's - but I heard the troubling sound of high voltage to > ground. Measuring the Millen connectors to ground revealed a short. Here > the Millen connectors on the modulator were arcing to ground on the > secondary side of the modulation transformer running from the high voltage > through the secondary winding to the PA amplifier. I am using those light > tan units that are supposed to be better than the red connectors. Stan used > these connectors on the PA amplifier, the modulator deck, and the high > voltage power supply. > > I suppose that under modulation that the peaks exceeded the voltage rating > of the Millen connectors. Once before many years ago, I had the same > problem. However, these connectors are often used in homebrew construction > projects as described in the ARRL handbook. > > Any ideas out there other than to go with ceramic feedthrough insulators. > > Perhaps, it is because of their age and the insulation is breaking down. > Who knows! > > Thanks > > Dave, W3ST > Publisher of the Collins Journal > Secretary to the Collins Radio Association > www.collinsra.com - the CRA Website > Now with PayPal > CRA Nets: 3805 Khz every Monday at 8 PM EST > and 14255 every Saturday at 12 Noon EST > > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
Re: [AMRadio] 7285Kc tomorrow/Saturday
A scope that produces the trapazopid patern is better for monitoring modulation! Bob Macklin K5MYJ Seattle, Wa. - Original Message - From: "John E. Coleman (ARS WA5BXO)" <[EMAIL PROTECTED]> To: "'Discussion of AM Radio'" Sent: Monday, January 09, 2006 7:13 AM Subject: RE: [AMRadio] 7285Kc tomorrow/Saturday I think what Mark is saying is that it it's difficult to tell what percentage modulation you're at when the wave form is not a sine wave and is not synced and this is true. You just have to get as close as you can with out pinching the carrier (not too often anyway). An automatic gain control circuit helps a lot with this. I did with out one for years learning how to talk by watching the scope. But it is a lot nicer and more relaxed when you have one. John -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of W5OMR/Geoff Sent: Monday, January 09, 2006 5:09 AM To: Discussion of AM Radio Subject: Re: [AMRadio] 7285Kc tomorrow/Saturday Mark K3MSB wrote: >Yes. I've tried a scope now and then (I have an old 60 Mhz B&K), but >truthfully I've never been able to really see when the modulation >level is 100% or other. I know what ideal waveforms look like (with >test inputs), but I have a hard time with a typical speech waveform. > I guess if I'm really at 20% that would be fairly easy to discern. >When I used the scope before I was trying to figure out how to tell if >I was say at 70%, 80%, 90% etc, and never felt I could do it >accurately. > Read the John/Don/Bacon page about asymetrical audio. It's written well, it's illustrated well, and completely discusses high-level, plate modulated audio and how much you -really- need. "Operating your AM Rig with out an oscilloscope, is like driving your car at night without headlights." (-K4KYV/Don Chester - AM Press Exchange) --- 73 = Best Regards, -Geoff/W5OMR __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
Re: [AMRadio] Millen High Voltage Connectors
Dave there are other makers of HV connectors out there. On their high power base stations, Motorola use a Teflon one. They are similar to one sold by Surplus Sales of Neb., see here: http://www.surplussales.com/Wire-Cable/HVWire-2.html The site says a pair are 14 for the Teflon type and the old style Millen tan colored are almost 20. The black are 15.60 Good luck & 73 Jim W5JO - Original Message - From: "david knepper" <[EMAIL PROTECTED]> To: ; <[EMAIL PROTECTED]> Sent: Monday, January 09, 2006 2:50 PM Subject: [AMRadio] Millen High Voltage Connectors My homebrew transmitter, designed by Stan, W3TGR now a silent key, is going through exhaustive and often frustrating testing. Stan used lots of shielded wire - you know the Belden stuff that is deteriorating over time with brittle insulation on the wire. I had to replace several leads because the center conductor was shorting to ground when the insulation became brittle. So it goes ... Today, I thought that I had finally debugged the unit - pair of 813's modulated by 805's - but I heard the troubling sound of high voltage to ground. Measuring the Millen connectors to ground revealed a short. Here the Millen connectors on the modulator were arcing to ground on the secondary side of the modulation transformer running from the high voltage through the secondary winding to the PA amplifier. I am using those light tan units that are supposed to be better than the red connectors. Stan used these connectors on the PA amplifier, the modulator deck, and the high voltage power supply. I suppose that under modulation that the peaks exceeded the voltage rating of the Millen connectors. Once before many years ago, I had the same problem. However, these connectors are often used in homebrew construction projects as described in the ARRL handbook. Any ideas out there other than to go with ceramic feedthrough insulators. Perhaps, it is because of their age and the insulation is breaking down. Who knows! Thanks Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com - the CRA Website Now with PayPal CRA Nets: 3805 Khz every Monday at 8 PM EST and 14255 every Saturday at 12 Noon EST __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
[AMRadio] Yaesu FT-101EX on AM
Greetings! I might be getting an FT-101EX and I have heard they do well on AM, if properly operated. This one is the EX model and of course needs the AM filter, but also needs crystals for 160 and two segments of 10 meters. Since I would most likely use it on 10, I wuz wonderin' if any of you know where I might get the required crystalsAND what's the frequency of the crystal(s)? I have read the manual and there doesn't seem to be any information about crystal frequency in there, or maybe I don't have a complete manual. Any of y'all usin' one for AM? Thanks es 73 de Dan -- WAØJRD ..
Re: [AMRadio] Millen High Voltage Connectors
Hi Dave, I solved the problem of HV B+ arc-overs here by exclusively using NOTHING but good-quality SO-239 coax receptacles, & RG-8 coax lines for the B+ leads, terminated in good-quality PL-259's... Works like the proverbial charm --- have yet to encounter ANY arc-over failures since adopting this approach universally at my station in the late 70's... ~73~ Eddy VE3CUI - VE3XZ PS: Emphasis on the words "...good-quality" --- NONE OF THAT CHINESE JUNK here!!! - Original Message - From: "david knepper" <[EMAIL PROTECTED]> To: ; <[EMAIL PROTECTED]> Sent: Monday, January 09, 2006 3:50 PM Subject: [AMRadio] Millen High Voltage Connectors > My homebrew transmitter, designed by Stan, W3TGR now a silent key, is > going through exhaustive and often frustrating testing. Stan used lots of > shielded wire - you know the Belden stuff that is deteriorating over time > with brittle insulation on the wire. I had to replace several leads because > the center conductor was shorting to ground when the insulation became > brittle. So it goes ... > > Today, I thought that I had finally debugged the unit - pair of 813's > modulated by 805's - but I heard the troubling sound of high voltage to > ground. Measuring the Millen connectors to ground revealed a short. Here > the Millen connectors on the modulator were arcing to ground on the > secondary side of the modulation transformer running from the high voltage > through the secondary winding to the PA amplifier. I am using those light > tan units that are supposed to be better than the red connectors. Stan used > these connectors on the PA amplifier, the modulator deck, and the high > voltage power supply. > > I suppose that under modulation that the peaks exceeded the voltage rating > of the Millen connectors. Once before many years ago, I had the same > problem. However, these connectors are often used in homebrew construction > projects as described in the ARRL handbook. > > Any ideas out there other than to go with ceramic feedthrough insulators. > > Perhaps, it is because of their age and the insulation is breaking down. > Who knows! > > Thanks > > Dave, W3ST > Publisher of the Collins Journal > Secretary to the Collins Radio Association > www.collinsra.com - the CRA Website > Now with PayPal > CRA Nets: 3805 Khz every Monday at 8 PM EST > and 14255 every Saturday at 12 Noon EST > > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb >
[AMRadio] Millen High Voltage Connectors
My homebrew transmitter, designed by Stan, W3TGR now a silent key, is going through exhaustive and often frustrating testing. Stan used lots of shielded wire - you know the Belden stuff that is deteriorating over time with brittle insulation on the wire. I had to replace several leads because the center conductor was shorting to ground when the insulation became brittle. So it goes ... Today, I thought that I had finally debugged the unit - pair of 813's modulated by 805's - but I heard the troubling sound of high voltage to ground. Measuring the Millen connectors to ground revealed a short. Here the Millen connectors on the modulator were arcing to ground on the secondary side of the modulation transformer running from the high voltage through the secondary winding to the PA amplifier. I am using those light tan units that are supposed to be better than the red connectors. Stan used these connectors on the PA amplifier, the modulator deck, and the high voltage power supply. I suppose that under modulation that the peaks exceeded the voltage rating of the Millen connectors. Once before many years ago, I had the same problem. However, these connectors are often used in homebrew construction projects as described in the ARRL handbook. Any ideas out there other than to go with ceramic feedthrough insulators. Perhaps, it is because of their age and the insulation is breaking down. Who knows! Thanks Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com - the CRA Website Now with PayPal CRA Nets: 3805 Khz every Monday at 8 PM EST and 14255 every Saturday at 12 Noon EST
[AMRadio] Wanted potentiometer, feed-thru capacitors
Hi guys; I need a few parts to finish up the linear amplifier I am building. I have checked all the parts catalogs I can find, with no luck on the potentiometer. I did find a feed-through at a price I can't afford. I need; 1 ea. 2500 ohm 25 watts or more potentiometer. 2 ea. 1000 pfd @ 500 or 600volts feed-through capacitor. * 2 ea. 1000pfd @ 1kv feed-through capacitors. * * 1/4" prefered as the 1/4" holes are already drilled. Thank you. 73, Ed Richards K6UUZ Simi Valley, Ca 93065 Home of the Air Force 1 pavilion
RE: [AMRadio] 7285Kc tomorrow/Saturday
Yes, Bill's voice and his Kenwood really sounds impressive. I heard Paul and Ashtabula Bill on the same? frequency, like they could not hear each other, both were very strong at my QTH. I try to stay off the air when Ashtabula Bill is on, he is typically VERY strong and wide. Its like having an ssb qso right on top of your frequency. Brett -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Todd, KA1KAQ Sent: Monday, January 09, 2006 11:27 AM To: Discussion of AM Radio Subject: Re: [AMRadio] 7285Kc tomorrow/Saturday On 1/8/06, Brett gazdzinski <[EMAIL PROTECTED]> wrote: Hey gang, just FYI > I worked KC2IFR (Bill), W3CRR (Craig), KA3ZLR (Jack) today, 40 was much > better than yesterday. > Bill has a very good sounding kenwood T599, one of those OLD kenwood twins, > but I suppose > some old SSB stuff was easier to get sounding good on AM then the new rigs, > maybe fewer filters > in the TX chain. His sounded very good and clean. Yep, heard you all quite nicely here in Central VT, have to ditto your remarks Brett about Bill's Kenwood. I know he has a lot of 'stuff' in line there, and the T599 seems to handle it all just fine. I was listening on the 75A-1 whilst dismantling the slain Christmas tree in the other room. Very pleasant audio. First time I've heard Craig's voice, was quite a shock after emailing for so long. Talk about a deep, 'radio' voice! I hope '2ZM got his transmitter audio problem solved. I was hearing him fine, but the audio was a little scruffy around the edges. I wrote it off to it being a 1930's tx, obviously it was something more involved. Also heard Ashtabula Bill getting a bit annoyed by Paul, who was apparently too close by for his liking. I suppose it's not as easy to spread out on 40 with all of the foreign BC and SSB activity around. The YL called and I was on the phone with her for a while and remember hearing The Nutcracker and other music coming across the frequency. Everyone did seem to drop out quickly. Of course, I only have about a ten foot piece of wire hooked onto the back of the A-1 right now, which probably doesn't help. Enjoyed it emmensely. Can't wait to join in again. de Todd/'Boomer' KA1KAQ __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
Re: [AMRadio] coils
On Mon, 9 Jan 2006, [EMAIL PROTECTED] wrote: Sand?? Doesn't this make it solid state??? klc Well, u - tube envelopes are made out of. ? Cheers John KB6SCO
Re: [AMRadio] coils
Sand?? Doesn't this make it solid state??? klc - Original Message - From: John Lawson <[EMAIL PROTECTED]> Date: Sunday, January 8, 2006 9:21 pm Subject: Re: [AMRadio] coils > > > > > > - Original Message - From: "Edward B Richards" > <[EMAIL PROTECTED]>>> > >> I am going to wind a pi section tank coil from 1/4" copper tubing > >> tomorrow. Mine will be 4" in diameter and 3" in diameter. Which > tubing is > >> best (no kink) thick or thin? Thanks. > > > A trick to making smooth bends in soft metal tubing, is to fill > it with > fine sand first. > > Now - I understand this can be tedious with long lengths of > small-diameter stock, but if you have no other mandrels or > fixtures to > wind it on, sometimes this can help from developing a kink in the > pipe. > Then, you can blow the sand out, or just leave it in there - > won't hurt > the electrical specs of the coil... > > Cheers > > John KB6SCO > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb >
RE: [AMRadio] 7285Kc tomorrow/Saturday
One way around the sync problem is to use the Trapezoid pattern by using scope in X:Y mode. That gives you different information but seeing > 100% + or - is easy to see, as is any non-linearity in the RF plate modulated amplifier. Of course if you have audio to the scope, and it's a dual trace scope, then you can stay on the RF envelope pattern, and trigger on the audio channel. You may need to adjust the trigger settings, and the sweep rate so that a "yea yea" into the Mic will always trigger and show a stable triggered pattern. I do both Trapezoid and envelope here. --- "John E. Coleman (ARS WA5BXO)" <[EMAIL PROTECTED]> wrote: > I think what Mark is saying is that it it's > difficult to tell what > percentage modulation you're at when the wave form > is not a sine wave and is > not synced and this is true. You just have to get as > close as you can with > out pinching the carrier (not too often anyway). An > automatic gain control > circuit helps a lot with this. I did with out one > for years learning how to > talk by watching the scope. But it is a lot nicer > and more relaxed when you > have one. > > John > > -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf > Of W5OMR/Geoff > Sent: Monday, January 09, 2006 5:09 AM > To: Discussion of AM Radio > Subject: Re: [AMRadio] 7285Kc tomorrow/Saturday > > Mark K3MSB wrote: > > >Yes. I've tried a scope now and then (I have an > old 60 Mhz B&K), but > >truthfully I've never been able to really see when > the modulation > >level is 100% or other. I know what ideal > waveforms look like (with > >test inputs), but I have a hard time with a > typical speech waveform. > > I guess if I'm really at 20% that would be fairly > easy to discern. > >When I used the scope before I was trying to figure > out how to tell if > >I was say at 70%, 80%, 90% etc, and never felt I > could do it > >accurately. > > > > Read the John/Don/Bacon page about asymetrical > audio. It's written > well, it's illustrated well, and completely > discusses high-level, plate > modulated audio and how much you -really- need. > > > "Operating your AM Rig with out an oscilloscope, > is like driving your car at night without > headlights." > (-K4KYV/Don Chester - AM Press Exchange) > > --- > 73 = Best Regards, > -Geoff/W5OMR > > __ > AMRadio mailing list > Home: > http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul > Courson/wa3vjb > > > > __ > AMRadio mailing list > Home: > http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul > Courson/wa3vjb >
[AMRadio] 40m, mystery band
Not everyone was hearing each other, typical 40 meter behavior. Blame it on the band. Had a nice 90 minute chat with Gary, WA4IAM on 7285Kc Saturday. He was 20-25+, and we soon slid down to 7280Kc where I then was able to open the receiver up a bit more. As an ex-broadcaster, Gary e has a nice mellow voice that sounds excellent on AM. I also heard Craig, W3CRR way down, apparently hooking up with Bill W8VYZ near where we were chatting. I later figured out that Craig and I may have called CQ at about the same time, 10A or so, and where Bill had heard and answered him, Gary had heard and answered me, with the resulting aforementioned mess. That's the mystery of 40 meters I guess. I came back ground 2P or so to check whether I could hear Dennis, QHO and any of the western stations, but nothing around. By 3 the international AM stations were coming in 10+ so I moved down low on 75m. There, had a great time with a trivia contest as to the "B" sides of various 45RPM records from the collection of Paul, K2ORC and his wife Peg. I didn't win any prizes, but the subject matter sprang from a schedule note -- prominent Buffalo AMer W2KBW, who works at Buffalo's WKBW, was going to be on 1520 later that night. Tom yesterday got on with us to discuss their sock-hop show. What a nice crossover between AM stations... Paul/VJB __ Yahoo! DSL Something to write home about. Just $16.99/mo. or less. dsl.yahoo.com
Re: [AMRadio] 7285Kc tomorrow/Saturday
On 1/8/06, Brett gazdzinski <[EMAIL PROTECTED]> wrote: Hey gang, just FYI > I worked KC2IFR (Bill), W3CRR (Craig), KA3ZLR (Jack) today, 40 was much > better than yesterday. > Bill has a very good sounding kenwood T599, one of those OLD kenwood twins, > but I suppose > some old SSB stuff was easier to get sounding good on AM then the new rigs, > maybe fewer filters > in the TX chain. His sounded very good and clean. Yep, heard you all quite nicely here in Central VT, have to ditto your remarks Brett about Bill's Kenwood. I know he has a lot of 'stuff' in line there, and the T599 seems to handle it all just fine. I was listening on the 75A-1 whilst dismantling the slain Christmas tree in the other room. Very pleasant audio. First time I've heard Craig's voice, was quite a shock after emailing for so long. Talk about a deep, 'radio' voice! I hope '2ZM got his transmitter audio problem solved. I was hearing him fine, but the audio was a little scruffy around the edges. I wrote it off to it being a 1930's tx, obviously it was something more involved. Also heard Ashtabula Bill getting a bit annoyed by Paul, who was apparently too close by for his liking. I suppose it's not as easy to spread out on 40 with all of the foreign BC and SSB activity around. The YL called and I was on the phone with her for a while and remember hearing The Nutcracker and other music coming across the frequency. Everyone did seem to drop out quickly. Of course, I only have about a ten foot piece of wire hooked onto the back of the A-1 right now, which probably doesn't help. Enjoyed it emmensely. Can't wait to join in again. de Todd/'Boomer' KA1KAQ
[AMRadio] WANTED: RBB RBC Parts, Ballast Tube
WANTED: Parts for the RBA-RBB-RBC radio receivers (US Navy WWII). Ballast Tubes--Amperite 6-80 Knobs of all sizes Power supply cables Power supply male connectors for cables Power supply female flange-mount connector (1) Meters Chart Frames Any help appreciated. Thanks. 73, Don Merz, N3RHT The information contained in this e-mail may be confidential and is intended solely for the use of the named addressee. Access, copying or re-use of the e-mail or any information contained therein by any other person is not authorized. If you are not the intended recipient please notify us immediately by returning the e-mail to the originator.(16b)
RE: [AMRadio] (no subject)
I have a 150 split stator and 250 single section caps. If possible, and if I can fit it in my box, I wouls like to have it cover 160. Going through the calculations. Will probably need a 3.5 or 4 in dia coil. Thanks for the suggestion, Greg W5RY -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mike Dorworth, K4XM Sent: Sunday, January 08, 2006 8:31 PM To: Discussion of AM Radio Subject: Re: [AMRadio] (no subject) Not sure exactrly what you want but B&W coil stock 8 tpi number 14 makes a wonderful tuner for 80 through 10 meter at full power. A piece 3 inch diameter 8 tpi number 14 is fine for 160 through 10 at full legal power. A 100 pf split stator in the first case a 200 in the second is sufficent for any know amateur use. I been using same for years. B&W will make them with Lexan Rods and they make wonderful 1 kw mobile coils.73 Mike - Original Message - From: "Greg Schultz Sr" <[EMAIL PROTECTED]> To: "'Discussion of AM Radio'" Sent: Sunday, January 08, 2006 10:02 AM Subject: RE: [AMRadio] (no subject) > I checked B&W site and they have coil stock but not large enough for > what I need. I am building a balanced link coupled tuner that can cover > at least 80 meters. > > Thanks, Greg W5RY > > -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Jim Wilhite > Sent: Saturday, January 07, 2006 8:35 PM > To: Discussion of AM Radio > Subject: Re: [AMRadio] (no subject) > > Greg the B&W ministock is still available. Is that what you are > seeking? > > http://www.bwantennas.com/ > > 73 Jim > W5JO > > > > > > > Does anyone know of a source for winding air core coils similar to the > > old B&W types?? I need two 2-3in diameter with about 60-70 turns for > a > > tuner - at least 12ga. There was a seller on ebay several months ago > > who wound coils to your specs but I lost his email address. Anyone > know > > of this person?? > > > > > > > > Greg W5RY > > > > __ > > AMRadio mailing list > > Home: http://mailman.qth.net/mailman/listinfo/amradio > > Help: http://mailman.qth.net/mmfaq.html > > Post: mailto:AMRadio@mailman.qth.net > > AMfone Website: http://www.amfone.net > > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > > > > > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > > __ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:AMRadio@mailman.qth.net > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
RE: [AMRadio] 7285Kc tomorrow/Saturday
I think what Mark is saying is that it it's difficult to tell what percentage modulation you're at when the wave form is not a sine wave and is not synced and this is true. You just have to get as close as you can with out pinching the carrier (not too often anyway). An automatic gain control circuit helps a lot with this. I did with out one for years learning how to talk by watching the scope. But it is a lot nicer and more relaxed when you have one. John -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of W5OMR/Geoff Sent: Monday, January 09, 2006 5:09 AM To: Discussion of AM Radio Subject: Re: [AMRadio] 7285Kc tomorrow/Saturday Mark K3MSB wrote: >Yes. I've tried a scope now and then (I have an old 60 Mhz B&K), but >truthfully I've never been able to really see when the modulation >level is 100% or other. I know what ideal waveforms look like (with >test inputs), but I have a hard time with a typical speech waveform. > I guess if I'm really at 20% that would be fairly easy to discern. >When I used the scope before I was trying to figure out how to tell if >I was say at 70%, 80%, 90% etc, and never felt I could do it >accurately. > Read the John/Don/Bacon page about asymetrical audio. It's written well, it's illustrated well, and completely discusses high-level, plate modulated audio and how much you -really- need. "Operating your AM Rig with out an oscilloscope, is like driving your car at night without headlights." (-K4KYV/Don Chester - AM Press Exchange) --- 73 = Best Regards, -Geoff/W5OMR __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
Re: [AMRadio] 7285Kc tomorrow/Saturday
Mark K3MSB wrote: Yes. I've tried a scope now and then (I have an old 60 Mhz B&K), but truthfully I've never been able to really see when the modulation level is 100% or other. I know what ideal waveforms look like (with test inputs), but I have a hard time with a typical speech waveform. I guess if I'm really at 20% that would be fairly easy to discern. When I used the scope before I was trying to figure out how to tell if I was say at 70%, 80%, 90% etc, and never felt I could do it accurately. Read the John/Don/Bacon page about asymetrical audio. It's written well, it's illustrated well, and completely discusses high-level, plate modulated audio and how much you -really- need. http://www.qsl.net/wa5bxo/asyam/aam3.html (guess the URL would help, eh? sorry 'bout that) "Operating your AM Rig with out an oscilloscope, is like driving your car at night without headlights." (-K4KYV/Don Chester - AM Press Exchange) --- 73 = Best Regards, -Geoff/W5OMR
Re: [AMRadio] 7285Kc tomorrow/Saturday
Mark K3MSB wrote: Yes. I've tried a scope now and then (I have an old 60 Mhz B&K), but truthfully I've never been able to really see when the modulation level is 100% or other. I know what ideal waveforms look like (with test inputs), but I have a hard time with a typical speech waveform. I guess if I'm really at 20% that would be fairly easy to discern. When I used the scope before I was trying to figure out how to tell if I was say at 70%, 80%, 90% etc, and never felt I could do it accurately. Read the John/Don/Bacon page about asymetrical audio. It's written well, it's illustrated well, and completely discusses high-level, plate modulated audio and how much you -really- need. "Operating your AM Rig with out an oscilloscope, is like driving your car at night without headlights." (-K4KYV/Don Chester - AM Press Exchange) --- 73 = Best Regards, -Geoff/W5OMR
