FM or PCM Whats the diff
04-21-2002, 02:02 AM
#76
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Just trying to be realistic Harry..
As for the 9Z, they come in PCM so a price comparison to a 12 channel PPM is not equitable..
IPD will have to stand on its own merits and that will take time..
As for regular PPM I find it works fine for my average glow plane but I do get occasional hits......
With an expensive gas plane it's worth it to me to spend for PCM.
Actually 2-PCM receivers per plane.. And it's not cheap but neither is the plane, That is why I go with PCM...
As for the 9Z, they come in PCM so a price comparison to a 12 channel PPM is not equitable..
IPD will have to stand on its own merits and that will take time..
As for regular PPM I find it works fine for my average glow plane but I do get occasional hits......
With an expensive gas plane it's worth it to me to spend for PCM.
Actually 2-PCM receivers per plane.. And it's not cheap but neither is the plane, That is why I go with PCM...
04-21-2002, 09:41 AM
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Oh Boy...
Cley: I really don't know the details on how Futaba handles bad frames. I suppose it is possible it could work several ways such as waiting for the next full frame or if any frame is good, including a compressed one, the rx processes it. I really don't know.
IPD Spinmiesters: As I understand it, IPD will lock you out under heavy interference. Even the multiplexrc.com web site claims that IPD and PCM produce similar results. The main push Multiplex voices is that IPD is faster than PCM, but since IPD will work with any PPM transmitter its really the TRANSMITTER that is faster because it is in PPM mode. IPD has nothing to do with it. But wait... didn't we just determine that Futaba PCM is faster than PPM... which means PCM can be faster than IPD. IPD's push about still having control during hits while there is no control with PCM is marketing BS as far as I'm concerned. Both PCM and IPD will get data to the rx during moderate interference. PCM will drop a few frames while IPD just widens the pulse tolerance. The net result is the same. Under heavy hits both IPD and PCM will lock out. The Multiplex site would lead one to believe that one hit sends PCM into failsafe. The only possible advantage I can see to IPD over PCM is that it will work on any PPM Tx and if designed well it would have better resolution than 1024 PCM, but considering that 1024PCM resolution is similar to the centering on all but the best servos the point is moot for the average flier. That leaves "it will work with any PPM transmitter." I've seen no actual evidence that IPD is "more advanced"... it is just more compatible. Cost? The cost for the Multiplex 4000 tx is $940. Maybe street is lower. But that is in the ballpark of a 10x and 9ZAP and from what I have seen the 9ZAP is vastly superior with respect to mixing, assigning switches and flight modes. The 12 Ch IPD rx is $180... same as a 9ch Futaba PCM. Don't get me wrong, I think IPD is fine but don't blow smoke up my you know what.
IPD Spinmiesters: As I understand it, IPD will lock you out under heavy interference. Even the multiplexrc.com web site claims that IPD and PCM produce similar results. The main push Multiplex voices is that IPD is faster than PCM, but since IPD will work with any PPM transmitter its really the TRANSMITTER that is faster because it is in PPM mode. IPD has nothing to do with it. But wait... didn't we just determine that Futaba PCM is faster than PPM... which means PCM can be faster than IPD. IPD's push about still having control during hits while there is no control with PCM is marketing BS as far as I'm concerned. Both PCM and IPD will get data to the rx during moderate interference. PCM will drop a few frames while IPD just widens the pulse tolerance. The net result is the same. Under heavy hits both IPD and PCM will lock out. The Multiplex site would lead one to believe that one hit sends PCM into failsafe. The only possible advantage I can see to IPD over PCM is that it will work on any PPM Tx and if designed well it would have better resolution than 1024 PCM, but considering that 1024PCM resolution is similar to the centering on all but the best servos the point is moot for the average flier. That leaves "it will work with any PPM transmitter." I've seen no actual evidence that IPD is "more advanced"... it is just more compatible. Cost? The cost for the Multiplex 4000 tx is $940. Maybe street is lower. But that is in the ballpark of a 10x and 9ZAP and from what I have seen the 9ZAP is vastly superior with respect to mixing, assigning switches and flight modes. The 12 Ch IPD rx is $180... same as a 9ch Futaba PCM. Don't get me wrong, I think IPD is fine but don't blow smoke up my you know what.
04-21-2002, 02:05 PM
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FM or PCM Whats the diff
I've read somewhere that Futaba PCM uses "Position Confirmation Commands" as well as "Movement Commands".
So the movement commands must be the difference data.. That would indicate to me that the 4bit data does move the servo but does not establish the finite position as the 10bit absolute data does... Maybe someone knows more about this stuff and can explain?
So the movement commands must be the difference data.. That would indicate to me that the 4bit data does move the servo but does not establish the finite position as the 10bit absolute data does... Maybe someone knows more about this stuff and can explain?
04-21-2002, 02:34 PM
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FM or PCM Whats the diff
Monkey Boy,
If you have ever took the time to look at a MC 4000 and its possibilities, you will soon realize that your statement about the Futaba 9 is vastly superior is a very far from the truth. Futaba and JR are both playing catching up. There is no comparison.
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If you have ever took the time to look at a MC 4000 and its possibilities, you will soon realize that your statement about the Futaba 9 is vastly superior is a very far from the truth. Futaba and JR are both playing catching up. There is no comparison.
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04-21-2002, 07:23 PM
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Where's the beef?
I've looked at the 4000 mc radio on the web site. It has some nice features that my ZAP dosen't such as a frequency scan, but I still belive the ZAP is more power in programming and I mentioned why in my last post. You keep saying the Multiplex is the best thing since sliced bread.... but where's the beef? I'm not saying I'm right, but I just don't know what makes Multiplex so good and no one will offer anything substantial... just insults to JR and Futaba.
04-21-2002, 10:37 PM
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FM or PCM Whats the diff
Hey Cley:
I think the difference between absolute, and relative change data is this. They absolute data contains an encoded # from 1 to 1024. This is the servo position for that channel (kanal on your link) I forget how many channels there were, but the absolute values for the first frame were the odd #'s, and the relative change channels were the evens. The relative change channels were a lot shorter in duration than the absolute ones. I believe this is because instead of the relative change channels being an encoded # from 1 to 1024, it is an encoded # that is the difference (or some coding scheme) between one of the absolute channels, and itself (ie 1 is tied to 2, 3 to 4 etc). The smaller # takes less bits. This is how they were able to speed it up. Each frame contains data for all servos, some is absolute, and some is determined from some coding scheme in conjuction with the absolute channels. On the next full frame they switch, the evens will be absolute. It has to be something like this, cause it says if a bit error is detected, then a 14.25 ms block is rejected. This means that a 14.25 ms block has to contain all data for all channels. The paragraph you qouted is kinda misleading. It leads you to believe that one frame has the absolute data, and the next has the relative change.
Alan
I think the difference between absolute, and relative change data is this. They absolute data contains an encoded # from 1 to 1024. This is the servo position for that channel (kanal on your link) I forget how many channels there were, but the absolute values for the first frame were the odd #'s, and the relative change channels were the evens. The relative change channels were a lot shorter in duration than the absolute ones. I believe this is because instead of the relative change channels being an encoded # from 1 to 1024, it is an encoded # that is the difference (or some coding scheme) between one of the absolute channels, and itself (ie 1 is tied to 2, 3 to 4 etc). The smaller # takes less bits. This is how they were able to speed it up. Each frame contains data for all servos, some is absolute, and some is determined from some coding scheme in conjuction with the absolute channels. On the next full frame they switch, the evens will be absolute. It has to be something like this, cause it says if a bit error is detected, then a 14.25 ms block is rejected. This means that a 14.25 ms block has to contain all data for all channels. The paragraph you qouted is kinda misleading. It leads you to believe that one frame has the absolute data, and the next has the relative change.
Alan
04-22-2002, 01:21 AM
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FM or PCM Whats the diff
Originally posted by Cley
...That would indicate to me that the 4bit data does move the servo but does not establish the finite position as the 10bit absolute data does...
...That would indicate to me that the 4bit data does move the servo but does not establish the finite position as the 10bit absolute data does...
Since every frame has absolute and difference data, if you reject one frame, you lose the reference for the difference values in the next. It could either drop the differences in the next frame, resulting in a two-frame hold for those channels and a one-frame hold for the others, OR use the last known value for those channels in the decoder. I really don't know which it does.
04-22-2002, 01:13 PM
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RE:
"I've read somewhere that Futaba PCM uses "Position Confirmation Commands" as well as "Movement Commands". "
-------------------------------------------------------------------------------
Looking back, I may have misinterpreted that...
"Movement Commands" may just mean that the transmitter sends the channels that have changed position more often than the ones that have not changed.
"Position Confirmation Commands" would be sent occasionally to the channels that have not changed position...............
BUT! The author of that aerodesign link does state that,
RE: Futaba PCM, "In the first frame an absolute value is sent , in the second one only the relative change."
Yeah, "Relative Change" from what? From the previous two frame message? or from the absolute data in the immediate prior frame?
or from a different channel position in the same frame?
I think that he should clarify more...
"I've read somewhere that Futaba PCM uses "Position Confirmation Commands" as well as "Movement Commands". "
-------------------------------------------------------------------------------
Looking back, I may have misinterpreted that...
"Movement Commands" may just mean that the transmitter sends the channels that have changed position more often than the ones that have not changed.
"Position Confirmation Commands" would be sent occasionally to the channels that have not changed position...............
BUT! The author of that aerodesign link does state that,
RE: Futaba PCM, "In the first frame an absolute value is sent , in the second one only the relative change."
Yeah, "Relative Change" from what? From the previous two frame message? or from the absolute data in the immediate prior frame?
or from a different channel position in the same frame?
I think that he should clarify more...
04-22-2002, 05:33 PM
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Re: Oh Boy...
Originally posted by MonkeyBoy
The cost for the Multiplex 4000 tx is $940. Maybe street is lower. But that is in the ballpark of a 10x and 9ZAP and from what I have seen the 9ZAP is vastly superior with respect to mixing, assigning switches and flight modes. The 12 Ch IPD rx is $180... same as a 9ch Futaba PCM. Don't get me wrong, I think IPD is fine but don't blow smoke up my you know what.
The cost for the Multiplex 4000 tx is $940. Maybe street is lower. But that is in the ballpark of a 10x and 9ZAP and from what I have seen the 9ZAP is vastly superior with respect to mixing, assigning switches and flight modes. The 12 Ch IPD rx is $180... same as a 9ch Futaba PCM. Don't get me wrong, I think IPD is fine but don't blow smoke up my you know what.
The main UK magazine did a survey a few months back of UK/European gliding competitions and found that in the Tx compound a staggering 80% of radios were Multiplex! I think you in the USA are being deprived of the more full choice we have of radios. Though it is interesting to see in here the number of people who use Hitec, hardly any shop in the UK will stock it and nobody will buy it because it has such an awful reputation!
Sounds like Mpx is overpriced in the USA compared to here, or more likely our Futaba/JR is grossly overpriced, and that gives us a very different angle on the choices.
Harry
04-22-2002, 05:53 PM
#85
Re: Re: Oh Boy...
Originally posted by HarryC
The main UK magazine did a survey a few months back of UK/European gliding competitions and found that in the Tx compound a staggering 80% of radios were Multiplex! I think you in the USA are being deprived of the more full choice we have of radios.
The main UK magazine did a survey a few months back of UK/European gliding competitions and found that in the Tx compound a staggering 80% of radios were Multiplex! I think you in the USA are being deprived of the more full choice we have of radios.
Must be a disipline thing, because very very few people flying F3A from around the world use Multiplex (or JR for that matter), almost everyone uses Futaba, for competition aerobatics Futaba reigns supreme.
04-22-2002, 06:38 PM
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FM or PCM Whats the diff
The problem that the MC 4000 has is that it is a Tray type TX and most North Americans prefer thumb flying. That is why Multiplex is coming out the new Royal EVO.
I don't know anyone that has tried Multiplex to ever want to go back to any others.
The ones that dislike Multiplex are the ones that have never tried them.
Volume does not make it better, case in point, a Chevrolet Chevette outnumbers the Mercedes by a long shot, but it is still a chevette.
Enough said.
I have tried them so I can speak.
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I don't know anyone that has tried Multiplex to ever want to go back to any others.
The ones that dislike Multiplex are the ones that have never tried them.
Volume does not make it better, case in point, a Chevrolet Chevette outnumbers the Mercedes by a long shot, but it is still a chevette.
Enough said.
I have tried them so I can speak.
Roger
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04-23-2002, 05:36 AM
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Hum...
I guess we all use what is easily obtainable. I only met one person who owns a multiplex radio... ever. Therefore, it won't be easy for me to "try one out" so to speak so I was hoping for some details other than "everyone else is playing catch up." Guess the point is moot anyway... already own two ZAPs. Seems like where I live the top fliers use JR... the lessers use Hitec and I use Futaba. If I look at what is being used in the states at major fly-ins, the masters, TOC, ect. there is a large population of JR and Futaba. I don't want to get into a my radio is bigger than yours conversation. Until I can actually use a multiplex I'll give it a rest. If I do decide to get a multiplex someday my sister lives in London... I'll have her pick it up for me if they are cheaper in Europe.
Back to PCM. With Futaba PCM, the first frame is an absolute servo possition for all channels. The second frame uses a differential compression for all channels. The frames alternate, one full, one compressed. Each frame (both full and compressed) have checksums for frame validation. This is very similar to how Digital Cable works. I'm sure there is other stuff going on such as occasionally the failsafe positions must be sent to the rx. I've noticed that my ZAP must be on for about 10 seconds before failsafe in the Rx works so the failsafe frames must be sent about once every ten seconds. At least this is what I believe to be happening from what I have experienced and read.
Back to PCM. With Futaba PCM, the first frame is an absolute servo possition for all channels. The second frame uses a differential compression for all channels. The frames alternate, one full, one compressed. Each frame (both full and compressed) have checksums for frame validation. This is very similar to how Digital Cable works. I'm sure there is other stuff going on such as occasionally the failsafe positions must be sent to the rx. I've noticed that my ZAP must be on for about 10 seconds before failsafe in the Rx works so the failsafe frames must be sent about once every ten seconds. At least this is what I believe to be happening from what I have experienced and read.
04-23-2002, 12:32 PM
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FM or PCM Whats the diff
"Back to PCM. With Futaba PCM, the first frame is an absolute servo possition for all channels. The second frame uses a differential compression for all channels. The frames alternate, one full, one compressed. Each frame (both full and compressed) have checksums for frame validation. This is very similar to how Digital Cable works. I'm sure there is other stuff going on such as occasionally the failsafe positions must be sent to the rx. I've noticed that my ZAP must be on for about 10 seconds before failsafe in the Rx works so the failsafe frames must be sent about once every ten seconds. At least this is what I believe to be happening from what I have experienced and read"
Not according to this. Each frame contains absolute and differential.
http://www.aerodesign.de/peter/2000/PCM/pcm_systeme.gif
Alan
Not according to this. Each frame contains absolute and differential.
http://www.aerodesign.de/peter/2000/PCM/pcm_systeme.gif
Alan
04-23-2002, 06:56 PM
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Your're Right...
Humph... Ok, what I believed was wrong. Looks like each 14.25ms frame contains absolute and differential data. The second frame is similar except the channels are reversed.
So then were does the failsafe data fit in? It that the refernce data block just before the checksum?
So then were does the failsafe data fit in? It that the refernce data block just before the checksum?
04-23-2002, 08:04 PM
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FM or PCM Whats the diff
To those people refering to the aerodesign.de website:
I don't think the Futaba/Robbe PCM frame structure as shown applies to Futaba 9Z, 8U, etc radios.
I looked at the PCM data stream on the DSC output of my 9ZWC. It didn't look anything like the 14.25/28.5 ms frame structure shown at
http://www.aerodesign.de/peter/2000/PCM/pcm_systeme.gif
From memory (I have it written down at home somewhere) the frames from the 9Z were 26 ms long, and they each contained four channels' data. It was easy to see which bits corresponded to each channel by moving the sticks and knobs while watching the scope.
It took two frames to update all eight channels, if that's what it wanted to do. There seemed to be some priority given to channels that were changing rapidly: these channels looked like they got some space in consectutive frames, at the expense of non-changing channels.
So, it would appear that an individual channel can be updated every 26 ms if required, but normally it would be every 52 ms. The 9Z WCII is supposed to do better than this under some conditions, but I don't have one to see what it does.
The channel 9 on/off state seemed to be transmitted by changing the coding (introducing deliberate coding errors?) into channel 8.
Every minute, all the channels would send a frame of different data to that commanded by the controls. I guess this was the failsafe update information.
Note that the Robbe version seems able to transmit channel 9 with full analogue capability. The 9Z and 9C can only transmit on/off on channel 9, with no ATV, trim, subtrim, or mixing.
Of course it may be that the DSC output (which can connect directly to a receiver, bypassing the RF link) has a different frame structure to the actual transmitted signal, and the receivers can decode either. To be sure, I'd have to poke around in a receiver to find the demodulator (FM detector) output.
I was doing all this in the hope of figuring out the coding Futaba used. I didn't get that far, except to determine that it's not simple binary coding. They appeared to be using some coding tricks to keep the RF BW down. It may also be that the coding is used for the error detection (like HDB3, B8ZS, or 8B10B). There is certainly some redundancy in the coding since the channel 8 data is also used for channel 9.
At that time I decided it was time to go home and get some dinner.
I don't think the Futaba/Robbe PCM frame structure as shown applies to Futaba 9Z, 8U, etc radios.
I looked at the PCM data stream on the DSC output of my 9ZWC. It didn't look anything like the 14.25/28.5 ms frame structure shown at
http://www.aerodesign.de/peter/2000/PCM/pcm_systeme.gif
From memory (I have it written down at home somewhere) the frames from the 9Z were 26 ms long, and they each contained four channels' data. It was easy to see which bits corresponded to each channel by moving the sticks and knobs while watching the scope.
It took two frames to update all eight channels, if that's what it wanted to do. There seemed to be some priority given to channels that were changing rapidly: these channels looked like they got some space in consectutive frames, at the expense of non-changing channels.
So, it would appear that an individual channel can be updated every 26 ms if required, but normally it would be every 52 ms. The 9Z WCII is supposed to do better than this under some conditions, but I don't have one to see what it does.
The channel 9 on/off state seemed to be transmitted by changing the coding (introducing deliberate coding errors?) into channel 8.
Every minute, all the channels would send a frame of different data to that commanded by the controls. I guess this was the failsafe update information.
Note that the Robbe version seems able to transmit channel 9 with full analogue capability. The 9Z and 9C can only transmit on/off on channel 9, with no ATV, trim, subtrim, or mixing.
Of course it may be that the DSC output (which can connect directly to a receiver, bypassing the RF link) has a different frame structure to the actual transmitted signal, and the receivers can decode either. To be sure, I'd have to poke around in a receiver to find the demodulator (FM detector) output.
I was doing all this in the hope of figuring out the coding Futaba used. I didn't get that far, except to determine that it's not simple binary coding. They appeared to be using some coding tricks to keep the RF BW down. It may also be that the coding is used for the error detection (like HDB3, B8ZS, or 8B10B). There is certainly some redundancy in the coding since the channel 8 data is also used for channel 9.
At that time I decided it was time to go home and get some dinner.
04-23-2002, 10:18 PM
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FM or PCM Whats the diff
So we have things like http://www.aerodesign.de/peter/2000/...M_PPM_eng.html
saying "This proves the general opinion that PCM has better range than PPM to be unfounded."
and "Sensivity to adjacent channels is usually worse than comparable PPM receivers. Care has to be taken when flying over a transmitter from an adjacent channel. "
Also http://www.torreypinesgulls.org/Radios.htm says "PCM does, unfortunately, have a serious Achilles heel weakness. Even minimal atmospheric or external noise can foul up those wonderful intricate binary numbers beyond any correction. In that case the receiver is up a creek without a paddle. The simple PPM pulses may be corrupted but some information generally gets through. The choice is between NO control (PCM) and some control (PPM). Most R/C flyers would prefer having some control even if erratic. "
So there is no clear cut case for PCM being unquestionably better than PPM. We'll never agree on this PPM/PCM debate with the current state of technology because there is no undeniably better system. PPM works fine for me and my clubmates, if PCM works for you then use it.
My thanks to Phil Cole's post above for confirming what I have found 9Z users to be cagey about admitting - it's really an 8 channel radio. I can smile even more benignly upon my Mpx true 9 proportional channel radio!
Harry
saying "This proves the general opinion that PCM has better range than PPM to be unfounded."
and "Sensivity to adjacent channels is usually worse than comparable PPM receivers. Care has to be taken when flying over a transmitter from an adjacent channel. "
Also http://www.torreypinesgulls.org/Radios.htm says "PCM does, unfortunately, have a serious Achilles heel weakness. Even minimal atmospheric or external noise can foul up those wonderful intricate binary numbers beyond any correction. In that case the receiver is up a creek without a paddle. The simple PPM pulses may be corrupted but some information generally gets through. The choice is between NO control (PCM) and some control (PPM). Most R/C flyers would prefer having some control even if erratic. "
So there is no clear cut case for PCM being unquestionably better than PPM. We'll never agree on this PPM/PCM debate with the current state of technology because there is no undeniably better system. PPM works fine for me and my clubmates, if PCM works for you then use it.
My thanks to Phil Cole's post above for confirming what I have found 9Z users to be cagey about admitting - it's really an 8 channel radio. I can smile even more benignly upon my Mpx true 9 proportional channel radio!
Harry
04-24-2002, 06:09 AM
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For Heaven Sakes...
The ZAP is a nine channel radio... the last channel is two state. Without the last channel my smoke wouldn't work so believe me the ninth channel is useful even if it is two state. For that matter I think the 10th channel on a JR 10x is only 512 PCM resolution... but I could be wrong. Gee... its too bad the Multiplex 4000 only supports five flight modes... Guess they had to ditch something to squeeze all those channels in... what was that called again? Evolution? OK, Sorry... me bad, but I couldn't resist.
I think both those web sites are a little off base. I have personally verifed that PCM appears to have better range at least during ground checks. We also have some pretty crappy weather here in Nebraska and I have never had any atsomopheric hits and I've even flown with thunder storms only a few miles away. Then again, what do I know... I'm just a monkey with a simple run of the mill 9ZAP
.
This thread makes me tired.
I think both those web sites are a little off base. I have personally verifed that PCM appears to have better range at least during ground checks. We also have some pretty crappy weather here in Nebraska and I have never had any atsomopheric hits and I've even flown with thunder storms only a few miles away. Then again, what do I know... I'm just a monkey with a simple run of the mill 9ZAP
.This thread makes me tired.
04-24-2002, 09:16 AM
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FM or PCM Whats the diff
This is a very interesting discussion. What if someone puts together a poll for all to answer. Lets see how the PPM/PCM "opinion" is distributed.
04-24-2002, 09:32 AM
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Monkeyboy, you want more than 5 flight modes! I struggle to cope with 3, I lose track of which mode I am in. Of course I would find it easier to cope with 5 modes in the 4000 since the optional speech module talks to you and tells you what mode you are in!
Serious question - what do you do with more than 2 modes? Is it only helicopters that use them or is there a real need in fixed wing aerobatics? I use a pattern and 3d mode and can't figure out what other modes I could want.
Harry
Serious question - what do you do with more than 2 modes? Is it only helicopters that use them or is there a real need in fixed wing aerobatics? I use a pattern and 3d mode and can't figure out what other modes I could want.
Harry
04-24-2002, 10:59 AM
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Flight Modes
Harry,
I also use a 4000, and use 2 flight modes and exactly for the reason you do. Patern and 3D.
When I switch to 3D, I gave it a .7 second delay so that it will take gently not to jerk the plane around if I happen not to be in perfect level flight. When I switch back to Pattern I gave it 0 seconds. Works beatifully. And what about those point curves on all channels???
Roger
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Fiber Optic Servo Extensions
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Model-Scan Frequency Analyzer
I also use a 4000, and use 2 flight modes and exactly for the reason you do. Patern and 3D.
When I switch to 3D, I gave it a .7 second delay so that it will take gently not to jerk the plane around if I happen not to be in perfect level flight. When I switch back to Pattern I gave it 0 seconds. Works beatifully. And what about those point curves on all channels???
Roger
ACM Rep....
Team ACM
Fiber Optic Servo Extensions
Forgues Propellers
Multiplex Dealer
http://www.aerografixs.com
Model-Scan Frequency Analyzer
04-24-2002, 11:40 AM
#97
04-24-2002, 11:41 AM
#98
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My Feedback: (7)
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FM or PCM Whats the diff
Ah, the EVO, unfortunately, it will not be availlable here for a while yet.
Roger
ACM Rep....
Team ACM
Fiber Optic Servo Extensions
Forgues Propellers
Multiplex Dealer
http://www.aerografixs.com
Model-Scan Frequency Analyzer
Roger
ACM Rep....
Team ACM
Fiber Optic Servo Extensions
Forgues Propellers
Multiplex Dealer
http://www.aerografixs.com
Model-Scan Frequency Analyzer
04-25-2002, 02:56 AM
#99
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PCM is better than PPM
Here's another link to the site that the Multi-Plex proponents (salesmen?) have referred us to...
http://www.torreypinesgulls.org/index.html
Notice who the Host Sponsor is??
One thing remains the same, PCM is better than PPM, IPD or otherwise.. Conflicting info about why it's better doesn't change the fact that it is...
As I said before Multi-Plex isn't even competetive in todays market IMO, they don't even carry PCM!
Time will tell eh?
http://www.torreypinesgulls.org/index.html
Notice who the Host Sponsor is??
One thing remains the same, PCM is better than PPM, IPD or otherwise.. Conflicting info about why it's better doesn't change the fact that it is...
As I said before Multi-Plex isn't even competetive in todays market IMO, they don't even carry PCM!
Time will tell eh?
04-25-2002, 03:51 AM
#100
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Mpx radios
A bit off topic, but Cley, I am curious about whay you say Mpx "isn't even competitive" in today's R/C market.
It's like saying Audi, Mercedes-Benz or BMW are not competitive in today's car market. Now, as cars go these are expensive, but people buy them. They are just not truly "mass market" products. They are competitive or they would go out of business. That is not going to happen any time soon, and I feel the same is the case with Mpx.
Also, just because they have not achieved huge market share (yet) in the US does not mean Mpx are not a well known and accepted R/C brand. In Europe and the UK Mpx radio's are reasonably commonplace, and here in Australia they are picking up market share, now they have a vigorous main agent who is keen to promote the virtues of the product.
It's blinkers off time. You may be correct about your comments on PCM, although as I mentioned on another thread Airtronics claim to have the worlds fastest 1024 PCM - a pretty bold claim if it is not true!
By the way, I don't fly Futaba or Mpx so I have no axe to grind. I have no particular brand loyalty. But I have to say you do seem very biased against Mpx products. That's your right of course. But it is better to stick to the facts when discussing the merits of products. Once upon a time, the highly respected Futaba was the new boy on the block ...
regards
fiery
It's like saying Audi, Mercedes-Benz or BMW are not competitive in today's car market. Now, as cars go these are expensive, but people buy them. They are just not truly "mass market" products. They are competitive or they would go out of business. That is not going to happen any time soon, and I feel the same is the case with Mpx.
Also, just because they have not achieved huge market share (yet) in the US does not mean Mpx are not a well known and accepted R/C brand. In Europe and the UK Mpx radio's are reasonably commonplace, and here in Australia they are picking up market share, now they have a vigorous main agent who is keen to promote the virtues of the product.
It's blinkers off time. You may be correct about your comments on PCM, although as I mentioned on another thread Airtronics claim to have the worlds fastest 1024 PCM - a pretty bold claim if it is not true!
By the way, I don't fly Futaba or Mpx so I have no axe to grind. I have no particular brand loyalty. But I have to say you do seem very biased against Mpx products. That's your right of course. But it is better to stick to the facts when discussing the merits of products. Once upon a time, the highly respected Futaba was the new boy on the block ...
regards
fiery