Re: [Repeater-Builder] ACSSB
This whole thread about ACSSB legality reminds me of read it again regarding TV channel 7 digital conversions of a few months ago. -- Original Message -- Received: Thu, 12 Nov 2009 07:47:54 AM PST From: wd8chl wd8...@gmail.com To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] ACSSB n0fpe wrote: One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band. I don't believe that comment on legality. But no, the reason there isn't bunch of those on the ham bands is that many people have tried with no success. The firmware in those doesn't allow out-of-band, and so far no one has had luck hacking it. And there isn't much value in doing it anyway. As Doug said, it didn't work very well, so why try?
Re: [Repeater-Builder] ACSSB
Interesting thing about part 97. It is written differently than any other part of the rules. In most of the rules they tell you what you can do and if it isn't specifically spelled out then you can't do it. In part 97 it is the other way around. For the most part they tell you what you can't do. So unless it specifically says you can't so it, it is assumed ok. This was done this way to promote experimentation with new modes and new ways to use old modes. I can't speak to this mode specifically but look at it technically as in bandwidth, modulation,... The tech specs that may exclude it from use, not the name or mode itself. JMO. YMMV. Rob Sent by Good Messaging (www.good.com) -Original Message- From: DCFluX [mailto:dcf...@gmail.com] Sent: Thursday, November 12, 2009 09:13 PM Eastern Standard Time To: Repeater-Builder@yahoogroups.com Subject:Re: [Repeater-Builder] ACSSB Could you please provide a rule number to back this up? Linear Modulation and ACSSB share 4K00J3E as the emission designator. On Thu, Nov 12, 2009 at 5:34 AM, n0fpe n0...@cox.net wrote: One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band. Since 1974, the award-winning Alpert JFCS has helped families of all faiths throughout most of Palm Beach County, FL, via counseling, seniors services, residences for the disabled, mentoring children, support groups and a lot more. SOLUTIONS FOR LIVING www.JFCSonline.com Please take note of our new website and E-Mail Addresses. Please update your contacts ASAP. . NOTICE: This e-mail message and all attachments transmitted with it are intended solely for the use of the addressee and may contain legally privileged and confidential information. If the reader of this message is not the intended recipient, or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any dissemination, distribution, copying, or other use of this message or its attachments is strictly prohibited. If you have received this message in error, please notify the sender immediately by replying to this message and please delete it from your computer.
RE: [Repeater-Builder] ACSSB
Agreed Rob. ACSSB is nothing more than regular old SSB with a few things added. The compandering is simply speech compression on the transmit end and an equivalent expansion on the receive end to restore the dynamic range of the voice. This gives some noise reduction in the circuit. As mentioned before the SEA radios placed the pilot tone in the middle of the band pass. The other guys just inserted some carrier (as I remember) for a pilot. This has been done for many years in the marine radio service on the SSB circuits. The carrier was run at 20 db down from peak power. The repeaters were licensed with a specific ERP and height above average terrain. So combiner loss, cable loss, antenna gain and height above average terrain were all factored in to determine the power output of the repeaters. The biggest problem was the cost of the equipment. They could not get the cost down to be competitive with FM. ACSB started out on the VHF bands with a few channels placed in-between FM two way channels. The problem there was too much interference from the FM side bands that clobbered the ACSSB receivers. Being amplitude based there is no capture or limiting like there is with FM so any little noise is heard. ACSSB can have much better range than FM with a clear channel (no noise) but it is hard to find such. SEA petitioned the FCC for a portion of the 220 band to get ACSSB only channels to get away from the problems with sharing with FM on the VHF channels. It was a good thought but the equipment had other problems, mostly manufacturing at reasonable cost. 73 Gary K4FMX _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Robert Pease Sent: Friday, November 13, 2009 8:01 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] ACSSB Interesting thing about part 97. It is written differently than any other part of the rules. In most of the rules they tell you what you can do and if it isn't specifically spelled out then you can't do it. In part 97 it is the other way around. For the most part they tell you what you can't do. So unless it specifically says you can't so it, it is assumed ok. This was done this way to promote experimentation with new modes and new ways to use old modes. I can't speak to this mode specifically but look at it technically as in bandwidth, modulation,... The tech specs that may exclude it from use, not the name or mode itself. JMO. YMMV. Rob Sent by Good Messaging (www.good.com) -Original Message- From: DCFluX [mailto:dcf...@gmail.com] Sent: Thursday, November 12, 2009 09:13 PM Eastern Standard Time To: Repeater-Builder@yahoogroups.com Subject:Re: [Repeater-Builder] ACSSB Could you please provide a rule number to back this up? Linear Modulation and ACSSB share 4K00J3E as the emission designator. On Thu, Nov 12, 2009 at 5:34 AM, n0fpe n0...@cox.net wrote: One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band. (Yahoo! ID required) Change settings via email: Switch mailto:repeater-builder-dig...@yahoogroups.com?subject=email%20delivery:%20 Digest delivery to Daily Digest | Switch mailto:repeater-builder-fullfeatu...@yahoogroups.com?subject=change%20deliv ery%20Format:%20Fully%20Featured to Fully Featured Visit http://groups.yahoo.com/group/Repeater-Builder;_ylc=X3oDMTJjdGcyZDNmBF9TAzk 3NDc2NTkwBGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDaHBmBHN 0aW1lAzEyNTgxMTcyMjE- Your Group | Yahoo! Groups http://docs.yahoo.com/info/terms/ Terms of Use | Unsubscribe mailto:repeater-builder-unsubscr...@yahoogroups.com?subject=unsubscribe
[Repeater-Builder] ACSSB
One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band.
Re: [Repeater-Builder] ACSSB
wonder why the fcc does not allow acssb above 30 mhz on the ham bands? seems to me they would want to promote more efficient modes through all the ham bands. another interesting thing would be to see 2 meter repeaters go to 2 or 3 mhz splits and employ some form of efficient modulation mode instead of the same old 10 khz fm. and i am sure we will be all dead before this happens :) one can imagine though. better tx/rx isolation, cleaner signals, employ some form of narrow band modulation scheme and we could even ease congestion on 2 meters. i still can't imagine how the 600 khz split was decided for 2 meters when there is room for at least a 2 mhz split. i like the idea of injecting the 100 hz tone into a ssb carrier and using it to lock the rit. - Original Message - From: n0fpe n0...@cox.net To: Repeater-Builder@yahoogroups.com Sent: Thursday, November 12, 2009 7:34 AM Subject: [Repeater-Builder] ACSSB One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band. Yahoo! Groups Links
Re: [Repeater-Builder] ACSSB
Rev. Robert P. Chrysafis wrote: wonder why the fcc does not allow acssb above 30 mhz on the ham bands? seems to me they would want to promote more efficient modes through all the ham bands. another interesting thing would be to see 2 meter repeaters go to 2 or 3 mhz splits and employ some form of efficient modulation mode instead of the same old 10 khz fm. and i am sure we will be all dead before this happens :) one can imagine though. better tx/rx isolation, cleaner signals, employ some form of narrow band modulation scheme and we could even ease congestion on 2 meters. i still can't imagine how the 600 khz split was decided for 2 meters when there is room for at least a 2 mhz split. duh-because when repeaters were first authorized for 2M, they were only allowed from 146 to 148. 144.5-145.5 didn't come into existence until the 80's. No-2M is too populated to do any changes. Not gonna happen until they just flat stop making FM gear. Not in my life time, not in your kids lifetimes, probably not in your grandkids lifetimes either. Same with the 150-174 LMR band...WAY to much gear out there to try to standardize input/output. Look at the bright side-at least the ham band HAS a standard. There is none in the LMR segment.
Re: [Repeater-Builder] ACSSB
n0fpe wrote: One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band. I don't believe that comment on legality. But no, the reason there isn't bunch of those on the ham bands is that many people have tried with no success. The firmware in those doesn't allow out-of-band, and so far no one has had luck hacking it. And there isn't much value in doing it anyway. As Doug said, it didn't work very well, so why try?
Re: [Repeater-Builder] ACSSB
I find nothing in Part 97 which would preclude ACSSB, as it appears to meet the definition of phone, but I do recall some debate at the time on whether the audio frequency inversion scheme/pilot tone was a form of scrambling/encryption, which would have made it illegal on the ham bands. The main benefit of that inversion was to preserve low-frequency audio response which normally is tough with a filter-based SSB exciter, and put the pilot tone at a frequency where it was easily processed and filtered, but hams are accustomed to narrow audio bandwidths and ducks talking, and there was no compelling reason to play with ACSSB. To some extent, ACSSB was simply the worst of all worlds, like NBFM with more ignition noise and companding artifacts, or SSB but restricted to channels. It made sense on paper as an analog bandwidth conservation tool compared to NBFM, but sounded really bad in areas of marginal signal, and who's still developing analog techniques these days? One reason for lack of interest in the mode I haven't seen mentioned was the incredible hostility generated among hams by the taking of 40% of the 220 MHz band to make commercial ACSSB happen. Just the mention of ACSSB at a club meeting would result in spontaneous aneurisms, even among hams who'd never operated on 220. Nobody wanted to be associated with ACSSB. We were too busy boycotting UPS! 73, Paul, AE4KR - Original Message - From: n0fpe To: Repeater-Builder@yahoogroups.com Sent: Thursday, November 12, 2009 5:34 AM Subject: [Repeater-Builder] ACSSB One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band.
Re: [Repeater-Builder] ACSSB
On Thursday 12 November 2009 07:34:08 n0fpe wrote: One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band. No, thats not true. There are ARRL publications on acssb; at one point it was seen as a complement to FM repeaters, being able to fit inbetween the 20KHz spaced channels of repeaters. I'm not sure that was ever workable, but there was some effort (by amrad?) to disperse acssb equipment on 2m and maybe higher bands. --STeve Andre' wb8wsf en82
Re: [Repeater-Builder] ACSSB
At 11/12/2009 07:47, you wrote: n0fpe wrote: One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band. I don't believe that comment on legality. Neither do I. IIRC ACSSB is nothing more than SSB with companding a pilot tone. The latter doesn't make the former a totally different mode. Bob NO6B
Re: [Repeater-Builder] ACSSB
Could you please provide a rule number to back this up? Linear Modulation and ACSSB share 4K00J3E as the emission designator. On Thu, Nov 12, 2009 at 5:34 AM, n0fpe n0...@cox.net wrote: One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band.
[Repeater-Builder] acssb - how does it work and is it possible for the hobbyist to scratch build
basically as the title states. i have never heard of acssb outside of 220-222 mhz. seems to me acssb was a good idea and was curious as to why the ham community has not picked up on it for mobile HF SSB use. seems to me having the benefits of SSB without the hassle of messing with a clarifier all the time has it's advantages in a mobile environment. also it seems running a AOR ARD9000 type device over ACSSB would be a really great advantage. i have zero experience with either of these modes so i am not sure how this idea would turn out. i know that the likely reason is NBFM and P25 for the demise of ACSSB, but as stated above seems to me it would be at home in the HF spectrum. I know i am going to get flamed for this, but i think ACSSB would make a great replacement for standard ssb in the 11 meter market. it would also allow the use of CTCSS on HF using a more efficient mode then FM. imagine haveing ACSSB 10 meter repeaters instead of FM.
Re: [Repeater-Builder] acssb - how does it work and is it possible for the hobbyist to scratch build
The demise of ACSSB in our area was the overall range was limited to poor sensitivity relative to a similarly situated uhf repeater.. Typical sensitivity of the mobiles was .4-.5~.6uv or so compared to sub .2uv on uhf and vhf fm mobiles that were readily available.. Sound quality did not help ... The noise floor is higher at 220 in many areas in the cities... compared to uhf basically our UHF systems killed 220 acssb once we could start trunking efficiently with LTR... there was no competition between the 2 as UHF engineered well was superior... It was not possible to improve the sensitivity of the front end due to the design of the hardware and systems typically could hear farther than they could talk... so mobiles lost the site first... Typically most systems were SEA that were actually getting loading... and those system cost a lot more for 100w amps than the stock 20w SO most systems were deployed with 20w transmitters at the site.. talking to 20w mobiles.. the site had a preamp on rx the combiners chewed up TX power ... lowering outbound ERP... Downlink power was always less than uplink. In FM 100w PA's are no issue to add at will to a 20w repeater.. boosting the output of an ACSSB transmitter required a complex amp with a feedback loop controlling gain $ not a $800.00 vocom or eq like on FM... We only owned one and never deployed it... it double the cost of each repeater... Performance was sub par for about any other radio operation including 800 mhzand probably 900 Doug KD8B At 03:46 PM 11/11/2009, you wrote: basically as the title states. i have never heard of acssb outside of 220-222 mhz. seems to me acssb was a good idea and was curious as to why the ham community has not picked up on it for mobile HF SSB use. seems to me having the benefits of SSB without the hassle of messing with a clarifier all the time has it's advantages in a mobile environment. also it seems running a AOR ARD9000 type device over ACSSB would be a really great advantage. i have zero experience with either of these modes so i am not sure how this idea would turn out. i know that the likely reason is NBFM and P25 for the demise of ACSSB, but as stated above seems to me it would be at home in the HF spectrum. I know i am going to get flamed for this, but i think ACSSB would make a great replacement for standard ssb in the 11 meter market. it would also allow the use of CTCSS on HF using a more efficient mode then FM. imagine haveing ACSSB 10 meter repeaters instead of FM.
Re: [Repeater-Builder] acssb - how does it work and is it possible for the hobbyist to scratch build
I was playing with the ideas of making adapters, but it is supprisingly difficult to throw audio exactly 90 degrees out of phase over a broad frequency range. Anyway it might be practical to adopt the pilot tone to an HF radio. I'd transmit a 100Hz pilot tone, or something that would go through the filters or even let a little of the carrier get transmitted and then on the receive side use something like a 4046 to generate the 100 Hz LO and then feed the output of the phase comparator back into the RIT control On Wed, Nov 11, 2009 at 2:17 PM, Doug Bade k...@thebades.net wrote: The demise of ACSSB in our area was the overall range was limited to poor sensitivity relative to a similarly situated uhf repeater.. Typical sensitivity of the mobiles was .4-.5~.6uv or so compared to sub .2uv on uhf and vhf fm mobiles that were readily available.. Sound quality did not help ... The noise floor is higher at 220 in many areas in the cities... compared to uhf basically our UHF systems killed 220 acssb once we could start trunking efficiently with LTR... there was no competition between the 2 as UHF engineered well was superior... It was not possible to improve the sensitivity of the front end due to the design of the hardware and systems typically could hear farther than they could talk... so mobiles lost the site first... Typically most systems were SEA that were actually getting loading... and those system cost a lot more for 100w amps than the stock 20w SO most systems were deployed with 20w transmitters at the site.. talking to 20w mobiles.. the site had a preamp on rx the combiners chewed up TX power ... lowering outbound ERP... Downlink power was always less than uplink. In FM 100w PA's are no issue to add at will to a 20w repeater.. boosting the output of an ACSSB transmitter required a complex amp with a feedback loop controlling gain $ not a $800.00 vocom or eq like on FM... We only owned one and never deployed it... it double the cost of each repeater... Performance was sub par for about any other radio operation including 800 mhzand probably 900 Doug KD8B At 03:46 PM 11/11/2009, you wrote: basically as the title states. i have never heard of acssb outside of 220-222 mhz. seems to me acssb was a good idea and was curious as to why the ham community has not picked up on it for mobile HF SSB use. seems to me having the benefits of SSB without the hassle of messing with a clarifier all the time has it's advantages in a mobile environment. also it seems running a AOR ARD9000 type device over ACSSB would be a really great advantage. i have zero experience with either of these modes so i am not sure how this idea would turn out. i know that the likely reason is NBFM and P25 for the demise of ACSSB, but as stated above seems to me it would be at home in the HF spectrum. I know i am going to get flamed for this, but i think ACSSB would make a great replacement for standard ssb in the 11 meter market. it would also allow the use of CTCSS on HF using a more efficient mode then FM. imagine haveing ACSSB 10 meter repeaters instead of FM.
