WOW! I just looked at this thread for the first time and read it all. :headbang For a minute or two I thought I had the television on and tuned to Comedy Central. :laugh:
Carry on carrying on!
Carry on carrying on!
-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
Got my Mauldulator today, WOW
- Thread starter wahlrite
- Start date
I am the person that designed the Mauldulator. My original interest in this circuit was exactly for 75M AM where I also operate. I do not operate on "the bowl", but I like tinkering around with MMM on projects like this.You will eventually be hearing this "gadget" on 75M AM, if only from my station. It is incompatible with my Johnson Valiant because of the voltages involved. It is incompatible with my Icom 706 which uses a balanced modulator stage to produce AM.
My long term goal is to use a Software Defined Radio board to put out about a 1 watt signal. I will then feed a home brew amplifier that can be "mauldulated". That amplifier will have an output of about 10-15 watts which will then drive another amplifier.
I will never run 200% modulation on this thing, although it can certainly do that. I may probably use up to 130%. It is true that most CB receivers can have unexpected results if the positive percentage is too high, and if the bandwidth is not paid attention to. MMM uses two receivers when customizing his audio going into this thing. He uses a stock Cobra 148 or Cobra 29 as well as a receiver with a wider pass band. He then adjusts it for the sound that is pleasing to him on both.
I use rack mounted equipment right now for my 75M AM stuff. I had that stuff going before I even knew about all this fancy software stuff. When I designed this thing I had no intention of using the computer because I did not even know about those audio processing programs. I admit that I like the idea of audio profiles that can be saved and loaded at will. I will probably not mess with the computer stuff until the latency is reduced. I like monitoring my AM signal in real time and the delay is too disorienting for me.
That being said, there are several stations that run computers in a high power environment. What do you think a Flex Radio is? MMM uses a pretty big box routinely and uses the computer just fine.
I think that a point is being lost in all of this discussion that I would like to emphasize. It is true that 200% positive modulation can be created, and that "high fidelity" can be achieved. The point I would like to make is that the Mauldulator presents you with a blank palette. What you put in is what comes out. Your audio is not reshaped by intentional limits of the radio or the undesired limitations of a modulation transformer. This functionality is important to some people, and not to others. If it is not important to you, then you don't need to buy it.
It also needs to be pointed out that broadcast AM stations are allowed to run 125% peaks, and they do so routinely. Furthermore, asymmetrical modulation is nothing new on the ham bands. During the peak of AM operation in the 50s and 60s on the ham bands, some hams played with so called "ultra modulation" and "negative cycle loading". Both of these implementations were basically the forerunners of today's negative peak clipping modifications on CB. While this will indeed result in signals with over 100% positive peaks, the cost is clipping of the negative side which causes distortion. Check out some of the ham references to this at The AM Press/Exchange Issue #65
Of course asymmetry is distorted by definition, but in the Mauldulator, the positive side of the audio is merely a larger version of the negative side. It is not clipped. I guess you could call this "less distorted distortion".
There have been critics insisting that you can duplicate the fidelity of the mauldulator on a simple radio using a proper microphone, or feeding a ham radio at the back in the auxiliary inputs. I would really like to see this.
Tink
Three easy steps to excellent CB Hi-Fi audio without a Mauldulator or PC connected to your radio.
1) Buy a Joemeek ThreeQ and a decent XLR mic.
2) Buy a cobra 148 GTL.
3) Connect the output of the Joemeek through a coupling cap to the base of the series pass modulator in the 148GTL.
No internal limitations of the CB. No modulation transformer. Most of all, no PC for simple audio processing. Notice most Flex radios recommend the use of specific Intel motherboards? Some even offer an RF proof PC as an option with the flex radio.
Let me know when you're going to be on 3.885 and I'll be happy to demonstrate Hi-Fi AM using a ricebox rig, 575M6 mic, and $10 worth of Radio Shack parts used to modify the transceiver and mic.
Maybe we need to formalize a definition for this term Hi Fidelity that is being thrown around. I would loosely define it as a faithful reproduction of the original. This would include the flatness of the response over a given range of frequencies, as well as a minimum of distortion added along the way. I would love to compare a radio with a mauldulator to your rice box. Would you like to do this sometime? I am sure we could put them side by side and compare the response curves and distortion products. It would be fun
Tink
Tink,
I know what Hi-Fi is and can easily achieve more bandwidth with flat response then we normally find on the broadcast bands. Once you know how to spot bypassing caps, coupling caps, and negative feedback loops in the audio chain, this is no difficult task.
Years ago I use to modulate radios from the outside using Hi-Fi stereo audio amps. Then I learned how to modify the radios internal audio stages to achieve the same results. It's a simple audio amplifier not rocket science. With a signal generator, a scope, and a schematic results are easy.
I enjoy AM and sharing what I've learned with others free of charge. At the recommendation of WA1HLR and W2NBC I will be posting one of my more popular modifications on the The AM Window site. The TS-940S is a very common radio that can be purchased used inexpensively now. You probably know they sound fairly bad on AM stock.
You don't need to travel all the way to Connecticut just to see mine. You can copy my modification and have you're very own. You can sweep it, look at it on the spectrum analyzer, and scrutinize the entire modification if you wish. Bottom line is it will provide every bit of fidelity you can get by modulating a rig from the outside and you can prove it to yourself.
The best part is my modification does not require the use of any external equipment that could introduce new places for RFI to migrate into the audio chain. Once the moderator on the amwindow site uploads the modification, I will post the links here. My documentation includes step by step instructions with photos. It renders old school outboard modulators obsolete by using Hi-Fi low level RF modulation as opposed to restricted IF modulation.
I know what Hi-Fi is and can easily achieve more bandwidth with flat response then we normally find on the broadcast bands. Once you know how to spot bypassing caps, coupling caps, and negative feedback loops in the audio chain, this is no difficult task.
Years ago I use to modulate radios from the outside using Hi-Fi stereo audio amps. Then I learned how to modify the radios internal audio stages to achieve the same results. It's a simple audio amplifier not rocket science. With a signal generator, a scope, and a schematic results are easy.
I enjoy AM and sharing what I've learned with others free of charge. At the recommendation of WA1HLR and W2NBC I will be posting one of my more popular modifications on the The AM Window site. The TS-940S is a very common radio that can be purchased used inexpensively now. You probably know they sound fairly bad on AM stock.
You don't need to travel all the way to Connecticut just to see mine. You can copy my modification and have you're very own. You can sweep it, look at it on the spectrum analyzer, and scrutinize the entire modification if you wish. Bottom line is it will provide every bit of fidelity you can get by modulating a rig from the outside and you can prove it to yourself.
The best part is my modification does not require the use of any external equipment that could introduce new places for RFI to migrate into the audio chain. Once the moderator on the amwindow site uploads the modification, I will post the links here. My documentation includes step by step instructions with photos. It renders old school outboard modulators obsolete by using Hi-Fi low level RF modulation as opposed to restricted IF modulation.
I was not interested in copying your modification, for I am happy with the results I already have. I was interested in a comparison. You made the claim that you can achieve hi fidelity with $10 in radio shack parts, implying that it would be comparable to to the Mauldulator. I am merely saying I would be interested in seeing the actual test in reality that you were discussing in words.
I have been modifying radios for years. I know my way around the coupling and bypass caps. We use the same concepts on the receiver end to improve their response, and I agree it is not rocket science. I am not critical of your work or your results, I am just responding to your comparison and I would like to see it happen. You mentioned having a flat response over a wider range than broadcast. I have no problem with that at all. The first night we got the Mauldulator functioning, we put in 30 KHz and saw the sidebands at the proper amplitudes on the spectrum analyzer. We can go as low as you like also. If you want to take out some filtering we intentionally put in, we can go to DC and you can use the audio in jack as a carrier control. You are not going to be able to do that very easily on most CBs by merely changing capacitors. Most of the audio stages are capacitively coupled and if you tried DC coupling, you would mess up the bias of the transistors something fierce.
I think it would be a fun test to compare the performance side by side. It looks like we are on opposite ends of the country, but if it could be worked out, I think it would be enjoyable.
Regards
Tink
I figured our locations would make it impractical to do your side by side testing and that's why I offered to get on 3.885. Even that probably will not work since east coast to west coast contacts their are rather difficult. Just like you I've had to add filtering after the modification because the response was from 1 cycle to nearly 100 KHz. This is no problem to do with stages that are capacitively coupled. Perhaps I can't get DC but getting the watt meter to go up and down at one cycle per second is not hard. You agree that is just as good as DC right?
The TA7222AP in the 148 GTL was designed as a stereo output chip. Surely you know it's able to reproduce Hi-Fi and the feedback loop from pin 9 (output) to pins 5 (gain adjust) and 6 (feedback) are what kills the high end. Test circuits given in the data sheet for this chip will show you how to easily configure it as an amp with flat response. Quite different from the stock circuit used in the Cobra. I'm interested in knowing what you think is going to prevent Hi-Fi modification here?
One main thing you seem to overlook is that there has never been a CB radio receiver manufactured that can reproduce lower then 200 cycles and higher then 4 KHz. Typical receiver response is 300 Hz to 3 KHz. At least on 75 meters there are receivers that can reproduce Hi-Fi. It's not very practical to think that everyone is going to modify their CB receivers to pass this bandwidth that essentially gets wasted on 11 meters.
The TA7222AP in the 148 GTL was designed as a stereo output chip. Surely you know it's able to reproduce Hi-Fi and the feedback loop from pin 9 (output) to pins 5 (gain adjust) and 6 (feedback) are what kills the high end. Test circuits given in the data sheet for this chip will show you how to easily configure it as an amp with flat response. Quite different from the stock circuit used in the Cobra. I'm interested in knowing what you think is going to prevent Hi-Fi modification here?
One main thing you seem to overlook is that there has never been a CB radio receiver manufactured that can reproduce lower then 200 cycles and higher then 4 KHz. Typical receiver response is 300 Hz to 3 KHz. At least on 75 meters there are receivers that can reproduce Hi-Fi. It's not very practical to think that everyone is going to modify their CB receivers to pass this bandwidth that essentially gets wasted on 11 meters.
I am not overlooking it, I am painfully aware of it. I don't use this on CB, other folks do. I have helped modify some receivers so that they can benefit from hearing the higher fidelity, but obviously the bigger crowd is going to miss out on the higher fidelity. This is a topic that I have discussed with MMM frequently.
Maybe I'll bump into you on a cold winter night on 3885. I hear those folks sometimes late on Saturday nights. We are mostly on 3870 on the west coast.
73 Tink
hello tink/shockwave,
theres no doubt most cb's without restrictive modulation transformers can do hifiwide audio on both tx and rx,
i demonstrated it to prime and mmm by direct injecting audio into the am modulator of an old cb from my wifes cd player headphone output and recording the audio received on my jrc receiver in wide am,
i did it because a bunch of superbowl guys were on paltalk claiming plastic cb's always sound plastic, i used primes song "no excuses on the bowl" which i thought was a fitting source material for superbowl naysayers,
i had been asking them for months if anybody had swapped filters and broadbanded the audio stages, i was amazed that in the land of AM cb none of them had changed any caps or fit wider filters in their plastic fantastic swingading radios,
though to myself i can make any plastic export do 10hz-20khz tx easy,
it took me all of 10 minutes to find an old ar144 and hook it up wideboy style,
even with the bandwidth restriction of the jrc's receiver and no tx eq it still made bass and trebble way beyond any stock cb transmitter as you would expect,
primes reaction was "gtfooh, that aint no plastic cb"
yes it was a plastic cb, it was just how i described it, prime called it a 4lbs globeking,
i had no eq at the time so it did not sound good to my ears but it did sound wide and not at all plastic,
next i swapped the stock 4kc am/ssb lattice filter in a second ar144 to a 15kc filter then rather than changing caps in the audio stages to broadband the rx audio i took a shortcut to hifi tapping audio straight from the am detector buffer and amplified it through a single ended tube hifi amp to get what most would describe as hifi am audio from a plastic cb,
first thing i noticed was that without audio tone shaping it sounds very wide but as flat as a kipper, needs some tx eq,
i played with it for a hour or so trying to figure out how to do asymetrical modulation which i knew tink and mmm were working on with the yet to be named prototype mauldulator then got bored and put it back in the garrage untill we get some good usa skip,
nobody in my area uses AM cb, even less want to listen to superwide AM cb transmissions, i am the AM lone ranger with nobody to bounce ideas off or listen to what im doing for some feedback,
having a deficit of power and a surplus of enthusiasm i have decided its easier and more efficient to inject audio from my datong asp,
i will slice through the wideboys like the grim reaper with my narrow intelligible rf processor
theres no doubt most cb's without restrictive modulation transformers can do hifiwide audio on both tx and rx,
i demonstrated it to prime and mmm by direct injecting audio into the am modulator of an old cb from my wifes cd player headphone output and recording the audio received on my jrc receiver in wide am,
i did it because a bunch of superbowl guys were on paltalk claiming plastic cb's always sound plastic, i used primes song "no excuses on the bowl" which i thought was a fitting source material for superbowl naysayers,
i had been asking them for months if anybody had swapped filters and broadbanded the audio stages, i was amazed that in the land of AM cb none of them had changed any caps or fit wider filters in their plastic fantastic swingading radios,
though to myself i can make any plastic export do 10hz-20khz tx easy,
it took me all of 10 minutes to find an old ar144 and hook it up wideboy style,
even with the bandwidth restriction of the jrc's receiver and no tx eq it still made bass and trebble way beyond any stock cb transmitter as you would expect,
primes reaction was "gtfooh, that aint no plastic cb"
yes it was a plastic cb, it was just how i described it, prime called it a 4lbs globeking,
i had no eq at the time so it did not sound good to my ears but it did sound wide and not at all plastic,
next i swapped the stock 4kc am/ssb lattice filter in a second ar144 to a 15kc filter then rather than changing caps in the audio stages to broadband the rx audio i took a shortcut to hifi tapping audio straight from the am detector buffer and amplified it through a single ended tube hifi amp to get what most would describe as hifi am audio from a plastic cb,
first thing i noticed was that without audio tone shaping it sounds very wide but as flat as a kipper, needs some tx eq,
i played with it for a hour or so trying to figure out how to do asymetrical modulation which i knew tink and mmm were working on with the yet to be named prototype mauldulator then got bored and put it back in the garrage untill we get some good usa skip,
nobody in my area uses AM cb, even less want to listen to superwide AM cb transmissions, i am the AM lone ranger with nobody to bounce ideas off or listen to what im doing for some feedback,
having a deficit of power and a surplus of enthusiasm i have decided its easier and more efficient to inject audio from my datong asp,
i will slice through the wideboys like the grim reaper with my narrow intelligible rf processor
Was just over reading posts at a forum run by Mojo, where Rickety Bones (MotorMouthMaul's) Partner posts on this topic.
I'm sure most everyone saw through this guys BS, but in case anyone had doubts here is a screen shot from a post where Rickety Bones was quoted, notice how Rickety Bones AKA Rick Adams, AKA Wahlrite, and probably every other new member who bragged about this device Signed his post...
I Believe you have to be logged in to see the posts, but the link is
Vbulletin messes with the link, even when in code tags so I've changed the HTTP to HXXP
Not sure if it can be edited, or if Mojo would help him by editing it... So the reference to wahlrite@gmail.com may disappear.
Before Rikety Bones started his dis-honest bombardment of Bullshit here, and on CBtricks forum I had considered buying one of these.
I knew it was him in all these Mauldulator threads Very Lame and Dishonest way to try and market your product.....
I'm sure most everyone saw through this guys BS, but in case anyone had doubts here is a screen shot from a post where Rickety Bones was quoted, notice how Rickety Bones AKA Rick Adams, AKA Wahlrite, and probably every other new member who bragged about this device Signed his post...
I Believe you have to be logged in to see the posts, but the link is
Code:
[URL="http://www.11meteroutlaws.com/viewtopic.php?f=39&t=275"]hxxp://www.11meteroutlaws.com/viewtopic.php?f=39&t=275[/URL]Not sure if it can be edited, or if Mojo would help him by editing it... So the reference to wahlrite@gmail.com may disappear.
Before Rikety Bones started his dis-honest bombardment of Bullshit here, and on CBtricks forum I had considered buying one of these.
I knew it was him in all these Mauldulator threads Very Lame and Dishonest way to try and market your product.....
Attachments
here again we see Rikety Bones AKA Wahlrite over at CBtricks trying to get Free advertising for his "snake oil"
Attachments
Last edited:
I sure am glad I don't have to pay you a commission, Fatty.
almost every order I receive, customers say things like " Man I just had to call " or " Whats up with the Mr. Fatty? Is he just a Hater or what ?"
Well anyways, thanks again, got to go sell more stuff!, jeep up the good work !
and thanks for the 3000+ views on the fourm,
almost every order I receive, customers say things like " Man I just had to call " or " Whats up with the Mr. Fatty? Is he just a Hater or what ?"
Well anyways, thanks again, got to go sell more stuff!, jeep up the good work !
and thanks for the 3000+ views on the fourm,
