RE: [AMRadio] Re: Carrier with one sideband
Vectors and resultant graphs are shown at this site http://www.qsl.net/wa5bxo/amtech.html John, WA5BXO __ 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] Re: Carrier with one sideband
I think most of the modern rice boxes are actually full double sideband. By modern, I mean in the last 5 years. I have not seen any lately that or not full double SB, but I am sure there are still a few that use the filter and are SSB with carrier insertion regardless of mode. Actually TV is a mix mode thing. The first 250KHZ of modulation is full AM DoubleSB but then the rest of the 4.1 MH of modulation is SSB. At 3.58MHZ is the suppressed color subcarrier (not transmitted except in bursts)with double Sideband I/Q addition out to 500KC above and below the 3.58MHZ mark then another 500KC upper but only at the phase that produces skin tone. At 4.5MHZ out is the full FM audio subcarrier that is 150KHZ wide Interestingly the IF bandpass of the TV RCVR is a bell or flat top shape with the main carrier tuned at 50% down on one slope and the 4.5MHZ audio subcarrier in a trap right before after the sound IF takeoff. John, WA5BXO -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Bob Macklin Sent: Thursday, February 07, 2008 5:39 PM To: Discussion of AM Radio in the Amateur Service Subject: Re: [AMRadio] Re: Carrier with one sideband The method of generating AM with a SSB transmitter by reinserting carrier was a common mode of operation in the late 50's and early 60's. The TV video signal works this way. It is my understanding the modern RICEBOXES that generate AM do it in the exact way. __ 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] Re: Carrier with one sideband
Gents: I have posted on my website for a short period of time a utility that I think will be of interest to those following this thread. Go to: http://tonnesoftware.com/ModTutor.exe It is mathematically sound and should be operable on most winnder$ computers. And it is of interest that most of the discussion here is confirmed by the program. - Jim WB6BLD __ 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] Re: Carrier with one sideband
Bill Breashear (sp) did an article in ER to convert an SB-401 to AM some time back. Jim WB2FCN Just dropping in - Original Message - From: John Coleman [EMAIL PROTECTED] To: 'Discussion of AM Radio in the Amateur Service' amradio@mailman.qth.net Sent: Friday, February 08, 2008 11:44 AM Subject: RE: [AMRadio] Re: Carrier with one sideband Vectors and resultant graphs are shown at this site http://www.qsl.net/wa5bxo/amtech.html John, WA5BXO __ 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] Re: Carrier with one sideband
Hi John, Actually almost all rice boxes since the late 80s or early 90s have had full DSB AM capability, 73, Ellen - AF9J Snip John Coleman [EMAIL PROTECTED] wrote: I think most of the modern rice boxes are actually full double sideband. By modern, I mean in the last 5 years. John, WA5BXO __ 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] Re: Carrier with one sideband
From: Peter Markavage [EMAIL PROTECTED] A number of the early phasing type transmitters/exciters and SSB adapters allowed you to operate on AM with just one sideband. So, only operating DSB AM would really be an issue. From: Bob Macklin [EMAIL PROTECTED] Any of the Heath SSB rigs (SB-100/101, SB-400/401, HW-100/101) could be modified to Vestigial SB. SSB with carrier reinserted. Bob Macklin K5MYJ SSB with the carrier re-inserted is not the same thing as what we know as AM. It is nothing more than SSB with poor carrier suppression. Reception with an envelope detector inherently generates severe distortion at modulation levels beyond about 20%. This mode is useful only with a receiver with BFO that locks onto the pilot carrier to eliminate frequency error in SSB reception, a technique that has in fact long been used in commercial services, with the carrier level reduced to about 20 dB below p.e.p. At modulation levels low enough to avert this distortion, known as quadrature distortion it is very wasteful of power since the sideband power becomes a very small percentage of total radiated power. Those amateur SSB rigs that transmit AM with carrier and one sideband sound like CRAP. Unless the receiving station is equipped with a proper receiver with PLL carrier reinsertion, which includes very few amateur receivers, it is a totally useless mode beyond simply getting someone's attention when they are receiving in AM mode, in order that they may switch the receiver over to SSB to receive the signal in normal SSB fashion. This problem is inherent to the principles of modulation, and has nothing to do with the quality of the equipment used. Transmitting AM with one sideband is NOT a solution to the problem nor is it even a satisfactory option. 73, Don k4kyv __ 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] Re: Carrier with one sideband
The method of generating AM with a SSB transmitter by reinserting carrier was a common mode of operation in the late 50's and early 60's. The TV video signal works this way. It is my understanding the modern RICEBOXES that generate AM do it in the exact way. I know it is not real AM but may people just don't have access to a good Johnson transmitter or DX-100. Bob Macklin K5MYJ Seattle, Wa, Real Radios Glow in the Dark - Original Message - From: D. Chester [EMAIL PROTECTED] To: amradio@mailman.qth.net Sent: Thursday, February 07, 2008 3:22 PM Subject: [AMRadio] Re: Carrier with one sideband From: Peter Markavage [EMAIL PROTECTED] A number of the early phasing type transmitters/exciters and SSB adapters allowed you to operate on AM with just one sideband. So, only operating DSB AM would really be an issue. From: Bob Macklin [EMAIL PROTECTED] Any of the Heath SSB rigs (SB-100/101, SB-400/401, HW-100/101) could be modified to Vestigial SB. SSB with carrier reinserted. Bob Macklin K5MYJ SSB with the carrier re-inserted is not the same thing as what we know as AM. It is nothing more than SSB with poor carrier suppression. Reception with an envelope detector inherently generates severe distortion at modulation levels beyond about 20%. This mode is useful only with a receiver with BFO that locks onto the pilot carrier to eliminate frequency error in SSB reception, a technique that has in fact long been used in commercial services, with the carrier level reduced to about 20 dB below p.e.p. At modulation levels low enough to avert this distortion, known as quadrature distortion it is very wasteful of power since the sideband power becomes a very small percentage of total radiated power. Those amateur SSB rigs that transmit AM with carrier and one sideband sound like CRAP. Unless the receiving station is equipped with a proper receiver with PLL carrier reinsertion, which includes very few amateur receivers, it is a totally useless mode beyond simply getting someone's attention when they are receiving in AM mode, in order that they may switch the receiver over to SSB to receive the signal in normal SSB fashion. This problem is inherent to the principles of modulation, and has nothing to do with the quality of the equipment used. Transmitting AM with one sideband is NOT a solution to the problem nor is it even a satisfactory option. 73, Don k4kyv __ 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] Re: Carrier with one sideband
The modern SS rigs do NOT generate AM in that manner. The last radio that I saw that used a carrier with ONE sideband for AM was the Collins KWS-1. That is precisely why I did NOT procure one when the opportunity arose. As to Vestigal SB, that INDEED is used in Amateur TV signals, however, I cannot remember whether it is for slow scan or fast scan. It eludes me at the moment, AND no carrier is used. Bob - NØDGN -- Bob Bethman/NØDGN/BC-610/Northern Radio SP-600 Manassas, VA - MultiBand Dipoles Bob Macklin wrote: The method of generating AM with a SSB transmitter by reinserting carrier was a common mode of operation in the late 50's and early 60's. The TV video signal works this way. It is my understanding the modern RICEBOXES that generate AM do it in the exact way. I know it is not real AM but may people just don't have access to a good Johnson transmitter or DX-100. Bob Macklin K5MYJ Seattle, Wa, Real Radios Glow in the Dark __ 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] Re: Carrier with one sideband
- Original Message - From: D. Chester [EMAIL PROTECTED] To: amradio@mailman.qth.net Sent: Thursday, February 07, 2008 6:22 PM Subject: [AMRadio] Re: Carrier with one sideband From: Peter Markavage [EMAIL PROTECTED] A number of the early phasing type transmitters/exciters and SSB adapters allowed you to operate on AM with just one sideband. So, only operating DSB AM would really be an issue. From: Bob Macklin [EMAIL PROTECTED] Any of the Heath SSB rigs (SB-100/101, SB-400/401, HW-100/101) could be modified to Vestigial SB. SSB with carrier reinserted. Bob Macklin K5MYJ SSB with the carrier re-inserted is not the same thing as what we know as AM. It is nothing more than SSB with poor carrier suppression. Reception with an envelope detector inherently generates severe distortion at modulation levels beyond about 20%. This mode is useful only with a receiver with BFO that locks onto the pilot carrier to eliminate frequency error in SSB reception, a technique that has in fact long been used in commercial services, with the carrier level reduced to about 20 dB below p.e.p. At modulation levels low enough to avert this distortion, known as quadrature distortion it is very wasteful of power since the sideband power becomes a very small percentage of total radiated power. Those amateur SSB rigs that transmit AM with carrier and one sideband sound like CRAP. Unless the receiving station is equipped with a proper receiver with PLL carrier reinsertion, which includes very few amateur receivers, it is a totally useless mode beyond simply getting someone's attention when they are receiving in AM mode, in order that they may switch the receiver over to SSB to receive the signal in normal SSB fashion. This problem is inherent to the principles of modulation, and has nothing to do with the quality of the equipment used. Transmitting AM with one sideband is NOT a solution to the problem nor is it even a satisfactory option. 73, Don k4kyv I agree with Bob that the phasing rigs sounded great on AM. Ive owned all the CE's from the 10A to 200V, a Lakeshore Phasemaster, and a HT-37. However I always ran them in the DSB position except for the 200V which was a cheapend up 100V. Ive been keeping a lookout for another 100V these days to keep company with the 75A4 and NCL-2000 Ive had since 1964. Worked a lot of DX and contests with that setup. Sold the 100V in the late 80's and been kicking myself since. Carl KM1H __ 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] Re: Carrier with one sideband
- Original Message - From: rbethman [EMAIL PROTECTED] To: Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Sent: Thursday, February 07, 2008 5:47 PM Subject: Re: [AMRadio] Re: Carrier with one sideband The modern SS rigs do NOT generate AM in that manner. The last radio that I saw that used a carrier with ONE sideband for AM was the Collins KWS-1. That is precisely why I did NOT procure one when the opportunity arose. As to Vestigal SB, that INDEED is used in Amateur TV signals, however, I cannot remember whether it is for slow scan or fast scan. It eludes me at the moment, AND no carrier is used. Bob - NØDGN It's in amateur fast scan TV Bob. 73, Ellen - AF9J __ 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] Re: Carrier with one sideband
rbethman wrote: The modern SS rigs do NOT generate AM in that manner. The last radio that I saw that used a carrier with ONE sideband for AM was the Collins KWS-1. That is precisely why I did NOT procure one when the opportunity arose. Swan did the same thing. There was a 'carrier null' adjustment on the front of the Swan 350C that I had (think the 270 and 500 had it, as well) but there was no real 'AM' mode, on the radio. With the carrier 'unbalanced', you could modulate the thing like AM and be heard on -some- diode detector type receivers. -- Driving your AM Rig without a scope, is like driving your car at night, without headlights. (K4KYV) -- 73 = Best Regards, -Geoff/W5OMR __ 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] Re: Carrier with one sideband
Gents: First, this is my first post to this interesting group and I hope you take what I have to say constructively. This business of SSB on AM, etc., is of interest to me on a technical basis. But let's do a computer simulation of this thing. To this end I have written a computer program which allows you to select various AM modes and the program then shows you the transmitted envelope and the associated spectrum. It is temporarily posted here: http://tonnesoftware.com/ModTutor.exe That file is just a barefoot executable without all of the usual Window$ garbage. It should run on most Windows computers. If not e-mail me and I'll make a full-blown install routine. I am suggesting you download the program and run it. Click on the opening screen option Single sideband and then click on Ideal lower sideband. See the transmitter output as a carrier. Then click on Carrier= 0 dB. Then on Carrier=-6 dB. Then on Carrier=-12 dB. Not real pretty, is it? Now click on Double sideband and on Carrier=0 dB. I think the folks on this group will find the routine as interesting as others have. - Jim WB6BLD __ 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] Re: Carrier with one sideband
- Original Message - From: jeremy-ca [EMAIL PROTECTED] To: Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Sent: Thursday, February 07, 2008 6:10 PM Subject: Re: [AMRadio] Re: Carrier with one sideband I agree with Bob that the phasing rigs sounded great on AM. Ive owned all the CE's from the 10A to 200V, a Lakeshore Phasemaster, and a HT-37. However I always ran them in the DSB position except for the 200V which was a cheapend up 100V. Ive been keeping a lookout for another 100V these days to keep company with the 75A4 and NCL-2000 Ive had since 1964. Worked a lot of DX and contests with that setup. Sold the 100V in the late 80's and been kicking myself since. Carl KM1H Carl, you have a Lakeshore Phasemaster?!! I've been looking for one of those for some time. You see, that radio is a part of the history of my hometown - Manitowoc, WI. Lakeshore Industries (named for the fact that the original factory [which is now a cannery] was close to the shore of Lake Michigan), who made this early phasing rig, was in my hometown. When I belonged to my hometown ham club in the 90s, some of the OTs were former movers and shakers at Lakeshore Industries. My old club has a couple of Phasemaster IIBs they're restoring for a vintage station (one of them was found 2 years ago, abandoned, in the last building Lakeshore industries was located in). I had a brief discussion with the designer of the Phasemaster rigs (Hubert Willis, W9TQV, if I remember right), about them back in 1997 (we were looking at the Phasemaster IIB, the club had on the shelf at the time). Those things are as rare as hens teeth, and my old club won't part with the extra Phasemaster II they have (yes I asked). 73, Ellen - AF9J __ 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] Re: Carrier with one sideband
Although not a true AM mode as the seasoned amateurs might define it, one sideband with carrier inserted, can work reasonably well, and does especially well in crowded band conditions. Actually Don, the last time we worked on 75 M, one early morning last Fall (or maybe late Summer), I was running the 100V with only one sideband and carrier inserted and driving a Johnson Courier amp. You must have had one of these special receivers because you never once mentioned anything unusual about the signal. Over the last several years of running the 100V, I never announce when I running one sideband, or double sideband, with carrier inserted when operating the AM mode. No one has ever commented on any unusual characteristics of the signal either way. If your in-country radio regulations limit you to a 3 KHz maximum bandwidth, going this route at least gets on the AM mode. Pete, wa2cwa On Thu, 7 Feb 2008 17:22:14 -0600 D. Chester [EMAIL PROTECTED] writes: SSB with the carrier re-inserted is not the same thing as what we know as AM. It is nothing more than SSB with poor carrier suppression. Reception with an envelope detector inherently generates severe distortion at modulation levels beyond about 20%. This mode is useful only with a receiver with BFO that locks onto the pilot carrier to eliminate frequency error in SSB reception, a technique that has in fact long been used in commercial services, with the carrier level reduced to about 20 dB below p.e.p. At modulation levels low enough to avert this distortion, known as quadrature distortion it is very wasteful of power since the sideband power becomes a very small percentage of total radiated power. Those amateur SSB rigs that transmit AM with carrier and one sideband sound like CRAP. Unless the receiving station is equipped with a proper receiver with PLL carrier reinsertion, which includes very few amateur receivers, it is a totally useless mode beyond simply getting someone's attention when they are receiving in AM mode, in order that they may switch the receiver over to SSB to receive the signal in normal SSB fashion. This problem is inherent to the principles of modulation, and has nothing to do with the quality of the equipment used. Transmitting AM with one sideband is NOT a solution to the problem nor is it even a satisfactory option. 73, Don k4kyv __ 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] Re: Carrier with one sideband
- Original Message - Subject: Re: [AMRadio] Re: Carrier with one sideband rbethman wrote: The modern SS rigs do NOT generate AM in that manner. Yes you're right - almost all SSB rigs from the 60s 70s basically were one sideband and a carrier. But since at least the mid 80s (with the exception of the Ten Tec Paragon II) all modern rigs do full DSB. It's just that they do low level AM, which is very dependent upon ALC level control (which can make then sound pretty nasty if you don't properly set up carrier levels). BTW, the FT-101 runs AM as one sideband with a carrier, IIRC. People have told me (and I heard a .wav file of some FT-101E transmissions verifying this), that if it's set up decently, it makes pretty good sounding AM. 73, Ellen - AF9J 73, Ellen - AF9J __ 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] Re: Carrier with one sideband
I said Ive owned one, that is past tense. I liked the phasing rigs so much I used them to drive transverters for VHF/UHF as well as one on 160M since the 100V didnt cover it at the time; I later found the 160 kit. The Lakeshore was a II model, not a B. I still have the Hetrodyning VFO which will be restored and used in a vintage AM station. You wouldnt happen to know of a source for the dial scale? Mine is a bit rough after the plastic face plate disintegrated. Since AM was still popular on VHF/UHF well into the 70's they were an easy way to get a decent signal and driving a KW linear on all modes. I sold all that gear off in the late 80's when I succumbed to a HF SS xcvr for the main HF station and to drive the transverters. I still use the Hallicrafters (much modified in the RX path) HA-2 and HA-6 to drive 1500W amps; cant kill the 5894's and they are so much more linear than a SS brick. Carl KM1H - Original Message - From: Ellen Rugowski [EMAIL PROTECTED] To: Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Sent: Thursday, February 07, 2008 7:57 PM Subject: Re: [AMRadio] Re: Carrier with one sideband - Original Message - From: jeremy-ca [EMAIL PROTECTED] To: Discussion of AM Radio in the Amateur Service amradio@mailman.qth.net Sent: Thursday, February 07, 2008 6:10 PM Subject: Re: [AMRadio] Re: Carrier with one sideband I agree with Bob that the phasing rigs sounded great on AM. Ive owned all the CE's from the 10A to 200V, a Lakeshore Phasemaster, and a HT-37. However I always ran them in the DSB position except for the 200V which was a cheapend up 100V. Ive been keeping a lookout for another 100V these days to keep company with the 75A4 and NCL-2000 Ive had since 1964. Worked a lot of DX and contests with that setup. Sold the 100V in the late 80's and been kicking myself since. Carl KM1H Carl, you have a Lakeshore Phasemaster?!! I've been looking for one of those for some time. You see, that radio is a part of the history of my hometown - Manitowoc, WI. Lakeshore Industries (named for the fact that the original factory [which is now a cannery] was close to the shore of Lake Michigan), who made this early phasing rig, was in my hometown. When I belonged to my hometown ham club in the 90s, some of the OTs were former movers and shakers at Lakeshore Industries. My old club has a couple of Phasemaster IIBs they're restoring for a vintage station (one of them was found 2 years ago, abandoned, in the last building Lakeshore industries was located in). I had a brief discussion with the designer of the Phasemaster rigs (Hubert Willis, W9TQV, if I remember right), about them back in 1997 (we were looking at the Phasemaster IIB, the club had on the shelf at the time). Those things are as rare as hens teeth, and my old club won't part with the extra Phasemaster II they have (yes I asked). 73, Ellen - AF9J __ 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] Re: Carrier with one sideband
Nice display Jim! But put it in the double side band position and reduce the carrier to -60 db or so and notice that you have exactly the same wave form as that of the SSB with carrier at -6db, which is equal to the side band energy in this case. It is not the transmission of the single side band with carrier that gives the distortion but the envelope detector in the receiver. With only one side band and carrier the detector can't make up its mind which signal is supposed to be the carrier and which is the modulation when you have higher levels of modulation. The result is high levels of second harmonic distortion generated in the detector. As long as the modulation percentage is kept to a lower level the distortion is minimal and it sounds fine. If you use a receiver with a rather sharp filter and listen to a regular AM signal and tune off to one side (which is often done when heavy qrm is present) you generate the same kind of signal at the detector in your receiver. You greatly reduce one side band of the signal reaching the detector and it sees SSB with carrier. 73 Gary K4FMX -Original Message- From: [EMAIL PROTECTED] [mailto:amradio- [EMAIL PROTECTED] On Behalf Of Jim Tonne Sent: Thursday, February 07, 2008 7:48 PM To: Discussion of AM Radio in the Amateur Service Subject: Re: [AMRadio] Re: Carrier with one sideband Gents: First, this is my first post to this interesting group and I hope you take what I have to say constructively. This business of SSB on AM, etc., is of interest to me on a technical basis. But let's do a computer simulation of this thing. To this end I have written a computer program which allows you to select various AM modes and the program then shows you the transmitted envelope and the associated spectrum. It is temporarily posted here: http://tonnesoftware.com/ModTutor.exe That file is just a barefoot executable without all of the usual Window$ garbage. It should run on most Windows computers. If not e-mail me and I'll make a full-blown install routine. I am suggesting you download the program and run it. Click on the opening screen option Single sideband and then click on Ideal lower sideband. See the transmitter output as a carrier. Then click on Carrier= 0 dB. Then on Carrier=-6 dB. Then on Carrier=-12 dB. Not real pretty, is it? Now click on Double sideband and on Carrier=0 dB. I think the folks on this group will find the routine as interesting as others have. - Jim WB6BLD __ 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] Re: Carrier with one sideband
I agree, modern radios (Kenwood etc) generate DSB with carrier that can be set to the proper level. All TV Stations, up to going digital, used VSB WITH carrier but only for the video. The voice was 25 KHz FM Dev. Charlie, 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] Re: Carrier with one sideband
Oh yes, I forgot to mention: VSB versus SSB versus real AM: VSB is NOT the same as SSB with carrier. VSB operates as DSB at lower modulating frequencies. As you raise the modulating frequency the signal becomes SSB. The reason VSB can sound better than SSB with carrier is that most of the modulating power is in the lower modulating frequencies and the usual diode demodulator handles that relatively well. - Jim WB6BLD __ 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] Re: Carrier with one sideband
Gary: Every single statement you made is true. SSB with one sideband sucks at high percentages of modulation. - Jim WB6BLD __ 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.
