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Panaxis AM Transmitter May Return

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Panaxis AM Transmitter May Return

I have teamed up with another broadcaster who knows Panaxis transmitters inside and out, in fact he was the one who provided Ernie the fixes for his FME FM transmitter back in the mid 80's. He also upgraded our AM transmitters by adding a trimmer cap for the crystal, and came up with a replacement for the MPF102 transistor that use to blow all the time. The transistors were also upgraded for improved output in our units, along with an improved power supply.

We are looking into recreating the Panaxis AM transmitter with the added modifications. If you ever owned a Panaxis, you know they were very loud, capable of 300% modulation. they also had a 50 ohm output and were not bothered by the presence of a FM transmitter like the Procaster and Sstran, regardless of power (We tested our Panaxis next to a 1000 watt FM transmitter), our Procaster will go into self oscillation in the presence of a 100mw FM. We are currently researching parts availability, and looking into adding PLL.

We think our recreated Panaxis will be far superior to the Ramsey AM25, and easier to build than the Sstran, along with a standard 50 ohm output which could used in carrier current.

With AM stations going dark in increasing numbers, and FM being crowded out, the market place needs more choices in AM transmitters that are a little easier on the budget. Not everyone can afford to shell out $800 for a certified transmitter.

We will keep you posted on what we come up with.

Steve
www.radiobrandy.com

a $700.00 transmitter gets

a $700.00 transmitter gets screwed up by a $100.00 100mW FM.

Damn.

Now the question is why? and does the rangemaster suffer from this flaw?

Thank You

--------------

Robert C. 

Warren / Sanders 2016

REV BoB Says: "a $700.00

REV BoB Says:

"a $700.00 transmitter gets screwed up by a $100.00 100mW FM.

Damn.

Now the question is why? and does the rangemaster suffer from this flaw?"

I says:

Huh? What the heck are you talking about?

Dade City Radio AM1610 & FM107.9, Part 15 John - WA4JM Owner-Operator-Chief Engineer-Program Manager http://wdcx.webs.com

As a former AM100 owner I'm excited!

The AM100 is what really got me started with 24/7 broadcasting! Building and operating that kit was entirely too much fun and I hope others will be able to enjoy that experience again.

I think one of the best features of the AM100 was that it was tough as nails. I probably hooked up every possible circuit backwards the first time and it just kept coming back for more.

If you're wondering what all the fuss is about, the original 1982 docs for the AM100 are located in our library, scanned as image files, here:

AM 100 plans package part 1

AM 100 plans package part 2

One thing I'd like to mention at this point as well is that all of the AM transmitters available to us now are, in my opinion, pretty remarkable. Just a few short years ago (well, 20 anyway, when I first became interested in AM part 15 broadcasting), there were very few options and none were affordable.

Now, thanks to the dedicated efforts of a few hardy vendors, the selection is really awesome. I feel quite strongly that there is no bad option these days, it's simply a matter of choosing the unit that's best for your needs.

What a great time for the hobby!

Experimental broadcasting for a better tomorrow!

Rangemaster Not Bothered

Robert, for some reason the Rangemaster is not effected by RFI from nearby FM broadcast in the 100 milliwatt range. After alerting Procaster to the problem, they were able to recreate it with a remote control used for model aircraft. I was told part 15 rules say you have to accept such interference.

Just plugging an XM radio into a Procaster, will send it into self osculation, I know it's not just the Procaster. Many Sstran users report the same problem, when it is used near an FM transmitter like the EDM.

One fix is to use an isolation transformer in the audio path, and ferrite beads on both the audio & power pack. sending a balanced signal over shielded cable helps a bit too.

Out of the box as shipped, plug your ears if you are near an FM transmitter when you turn it on!

The Panaxis AM transmitter for some reason is completely immune to RFI. Now the Panaxis FME 500 is a different story, it can't be operated around a 40 watt AM transmitter or it goes bonkers.

Steve
Radio Brandy

KNJO Radio, Radio Brandy, Radio Outlaw, Outlaw Radio, XRQK, XRQK FM, AV News Talk, KKTO, KGOE, KDNF, Rave HD. Did time in Los Osos, San Luis Obispo, Thousand Oaks, Simi Valley, The High Desert, Las Vegas, Needles, Victorville, Glendale, Ridgecrest.

Panaxis AM 100

Here is what the stock Panaxis AM 100 looks like for those who havent seen one.
http://i425.photobucket.com/albums/pp339/JoeChezk/100_3247.jpg
Radio Joe

Radio Joe

Procaster has been improved

After adding RF filtering on the audio, power and modulator, we believe we have fixed the interference issues that plagued the earlier units. It's not until you get some out in the field in different situations that these problems become known. We are always looking to improve our product and if you come across anything you think is not working as it should be, we would be glad to know about it.

Gerry
www.chezradio.com
Airwave Freedom

AM Built Like A Rock

"best features of the AM100 was that it was tough as nails."
You're right! You really had to work at it, to kill the AM100.
I had a pair with the 5 watt amp added, one was intended for standby. The standby saw very little service as the main ran 24/7 for five years and only needed the transistors changed out on the exciter a couple times from we driving them hard at +- 15 volts and the full 300% modulation the AM100 was capable of. Our transistors were all socketed, so changing them out was easy.

Each transmitter has its place, for an example: The Procaster is best for on the go legal broadcasting; like covering school football and softball games. The Procaster travels well and is easiest to tune up on the road and in tight spot like an attic. No need to drag the VOM around or a Inovonics 222 Audio Broadcast Limiter; just a screwdriver and crescent wrench for the U-Bolts will do.

The Rangemaster is the standard for commercial and government installations like schools etc. While it takes a bit more to tune up a Rangemaster, the results are worth it with greater range. Serviceability is also a plus with the IC's all socketed, if some reason you would need to change one out. It also makes an easier sale for government installations; because it is American made.

Sstran is great for those on a budget, and are comfortable with a soldering iron and building kits. Add Carl's antenna and it will cover a pretty good distance.

Back in March 1983 when I bought my first AM100, you had a choice of a LPB very expensive or the Panaxis AM100 under $100 bucks. The Graymark 505 AM transmitter had already disappeared from the marketplace long ago.

Who is not looking forward to the long anticipated AM Max3 from PCS? It will be great for carrier current operation for those confined to MDU's or restricted by CCR's.

The Myth that young people won't listen to AM is false! If you involve them in it, they will come!

Ernie really did change broadcasting for the better, How many of us got our feet wet on Ernie's transmitters? And bought his books? Imagine where we would be without Panaxis.

Long live Panaxis!

Steve
Radio Brandy

KNJO Radio, Radio Brandy, Radio Outlaw, Outlaw Radio, XRQK, XRQK FM, AV News Talk, KKTO, KGOE, KDNF, Rave HD. Did time in Los Osos, San Luis Obispo, Thousand Oaks, Simi Valley, The High Desert, Las Vegas, Needles, Victorville, Glendale, Ridgecrest.

Bugs Never Show Up In The Lab!

The Panaxis transmitters had their share of bugs that were only discovered in the field by us. Lucky for me, I had a genius when it came to Panaxis transmitters: AM & FM. Ernie would promptly incorporate the fixes into his plans and kits, and would also send out update kits. For the AM; the MPF102 would pop with the wrong Crystal or when you tried to tweak the Crystal with a trimmer cap. The FME FM transmitter clashed with the stereo generator, a tone could be herd in the background. A cap in the right place under the board and a few parts changed out corrected that problem.

Not all bugs are bad:
Some bugs can lead to great discoveries; without the bug in the Procaster, I would have never discovered that the Procaster is outstanding for horizontal attic installs. If was from that attic install, that I learned what a great transmitter the Procaster is for taking on the road. I figured if was that easy to mount and tune in a cramped attic, it would also be in the field.

Allot of sports and special events have been broadcast with the Procaster on site. People like the nostalgia of being able to bring a radio to the game where their kids are playing. You would be surprised how easy it is to find someone to do play by play on the radio. After the game, people come up to us taking interest in the transmitter asking questions about how and where they can get one.

When the economy turns around, don't be surprised if Procaster sales start to spike in the west. Who knows! The downturn might even be good for transmitter sales, as people have to find new ways to make money, and business needs lower cost ways to advertise.

I'm glad to hear the bug has been dealt with on the manufacturing end. It will make allot easier to sell the Procaster as the transmitter for non technical types & The Special Events transmitter of choice.

Perfect place to debug a transmitter:
If you ever see the documentary "Who Killed The Electric Car"available on DVD. They do a scene at the Willow Spring Raceway in Rosamond California; on some camera angles, you will see a radio tower in the background. That tower is 3000watt 93.5FM, and it had kept us from using the Procaster there for races, obviously a racetrack is a perfect place for the Procaster, thanks to that tower we were forced to solve the problem.

Turns out the Willow Spring Raceway is not only a great place to test out cars but transmitters too! Ground conductivity is great there too!

Steve
Radio Brandy

KNJO Radio, Radio Brandy, Radio Outlaw, Outlaw Radio, XRQK, XRQK FM, AV News Talk, KKTO, KGOE, KDNF, Rave HD. Did time in Los Osos, San Luis Obispo, Thousand Oaks, Simi Valley, The High Desert, Las Vegas, Needles, Victorville, Glendale, Ridgecrest.

Panaxis Products

Since we are on the subject of Panaxis, are some of my Panaxis kits which I have that I built back in the early 80s . I called Ernie Wilison a few times when making these at the time. He always was willing to help. I learned a lot about transmitters from Mister Wilson. I bought a lot of his books also.

http://i425.photobucket.com/albums/pp339/JoeChezk/100_3305.jpg Power supply
http://i425.photobucket.com/albums/pp339/JoeChezk/100_3274.jpg FME 2000 2 Watt Transmitter
http://i425.photobucket.com/albums/pp339/JoeChezk/100_3209.jpg FMA 2000 2 Watt FM Amplifier
http://i425.photobucket.com/albums/pp339/JoeChezk/100_3198.jpg SG Stereo Generator
http://i425.photobucket.com/albums/pp339/JoeChezk/100_2469.jpg AM 5000 AM BC 5 Watt Amplifier
http://i425.photobucket.com/albums/pp339/JoeChezk/100_3247.jpg AM 100 100 MW BC Transmitter

.

Radio Joe

Thanks Radio Joe For The Great Pictures

Not only great photos Joe, but outstanding workmanship on your part. The cases that came with the Panaxis kits were less than ideal. The metal was real soft, which made it a little ruff when you pushed a button the whole front would bend.

Your photo of the AM100 reminded me of one part that may be hard to come by and that is the trimmer cap for tuning. I think Ernie was having a hard time finding them back then.

I just made contact with my engineer after 23 years, I'm sure he will be on this board soon. He thinks we can pull off the recreation of the AM100, the trimmer cap should not stand in our way.

Keep in mind the AM100 is not intended as a substitute for the Procaster or Rangemaster. It's intended for those who can't afford a Procaster or Rangemaster yet and don't mind a limited choice in frequencies in an a kit that is a little easier than the Sstran. The AM100 would make a nice building block for carrier current station.

Work in progress
Steve

KNJO Radio, Radio Brandy, Radio Outlaw, Outlaw Radio, XRQK, XRQK FM, AV News Talk, KKTO, KGOE, KDNF, Rave HD. Did time in Los Osos, San Luis Obispo, Thousand Oaks, Simi Valley, The High Desert, Las Vegas, Needles, Victorville, Glendale, Ridgecrest.

Panaxis items online: AM BCB Amplifier plans and Antenna book

Experimental broadcasting for a better tomorrow!

check out the library. there

check out the library. there is tons of technical info there from panaxis and the late pastor jr cunningham.

Thank You

--------------

Robert C. 

Warren / Sanders 2016

Correction on Panaxis FME Transmitter

The FME Transmitter put out either 250 MW or 500 MW depending on how it was configured, I was wrong on posting it as a 2 Watt transmitter. The actual name of it was the FME 250 and FME 500, And thanks for the comments on the pictures, When I built these I made sure all resistors even lined up with the tolerance band all facing the same direction ! The cases are Bud Boxes, not the ones from Panaxis as pointed out. The trimmer cap on the AM transmitter you can get those yet, from a few sources, I think Electronic Goldmine or similar outlets will have them, I have seen them all over actually just have to look for them.
Radio Joe

Radio Joe

Panaxis Items Online

Thanks for posting the AMA5000 and other Panaxis treasures online. Way back in the late 80's; Ernie had told me the iron cores were not available. If we could find them and the transistors are still available, I would make that amp a high priority for recreation too. If you have to do carrier current on the cheap, the AMA5000 is a must!

The phone companies must have made a small fortune from all of us seeking Ernie's help. My mother would blow a fuse when the phone bill arrived!

Steve
Radio Brandy

KNJO Radio, Radio Brandy, Radio Outlaw, Outlaw Radio, XRQK, XRQK FM, AV News Talk, KKTO, KGOE, KDNF, Rave HD. Did time in Los Osos, San Luis Obispo, Thousand Oaks, Simi Valley, The High Desert, Las Vegas, Needles, Victorville, Glendale, Ridgecrest.

Panaxis AM-100 Quick Observations

1. Don't forget you will need a loading coil. The AM-100 output has no tuning and wants to see a low impedance. This is what you get with a series loading coil.

2. Watch out how you interpret the "300% modulation" claim. Actually the plans are quite detailed in describing this feature. 300% modulation is achieved by dynamic power increase. Power increases as the square of voltage, so increasing the peak voltage by 3X increases the power by 9X. A continuous tone modulation at the 300% voltage level is equivalent to increasing the DC power input to 900 mW. The waveform shown in Fig. 6D in part 2 of the plans (and the field strength reading) is the same as you would get with 100% modulation of a 900 mW transmitter.

I read somewhere on the web about an older commercial AM transmitter that had some degree of dynamic carrier power control to increase the carrier power on audio peaks. Present-day (and most older) commercial AM transmitters don't do that, so I guess the FCC didn't like the idea.

Phil B

AM 100

I built up the AM 100 without the modulation boost in place, At the time discussions were about the distortion it added, and on top of it my knowledge (at the time) of loading coils and proper antenna really wasent that great, so the performance I was getting was like any AM 100 MW transmitter with a ten foot piece of wire without a loading coil, which is in most cases gives about five feet of range.. anyway I havent fired up the AM 100 for some years, I went FM years ago, but now back into AM and know the loading coil is very important and they are easy to build, so am anxious to try the AM 100 again to see what it will do. Of course this means taking it out of that nice box and unsoldering some wires, I hate to burn up someting in the process to convert to positive modulation to get the 300%.
Has anyone used one of these transmitters with a proper loading coil running the transmitter in the 300% mode?
Back then, I built the transmitter and got very short range with it because of a poor antenna system I was using, and like ohters who tired AM, I got discouraged and gave up on it.
I do remember the crystal clear sound of the transmitter. Tuning it up with a 50 ohm dummy load using a scope, all the wave forms looked good and the power checked out where it was supposed to be, Everything was correct, but the problem was the piece of wire comming off the antenna jack. Just a piece of wire and no loading coil didnt do the transmitter justice, years later I figured it all out how to do the antenna system correctly.
By the way, can anyone look at the schmatic of the push pull power amp on the AM 100 and tell me how to convert just that stage to 12-15 volts ( non split power supply) if I made just the amp part? Right now the amp is made for a split 15 volt + and 15 Volt - power supply, with ground ( common )through the bias network it looks like. I would like to take the power amp section and make a small stand alone amp for other LPAM projects, it looks like the parts and circuit shoud be good for at least 500MW ( for a lab amp of course). Ernie liked his split power supplies.

Radio Joe

New LPAM Antenna Requires 50 ohm

There is a new LPAM antenna at our test facility undergoing test, the antenna requires a 50 ohm input. That is part of the motivation for bring back the AM 100 which has a 50 ohm output. The AM100 as designed built like a rock with fairly common parts and a relatively simple design that should be easy for most kit builders on a tight budget.

Anyone who has owned one, will tell you the transmitter has allot of punch to it. Our AM100's were driven hard and still had a great big bottom sound without distortion.

If the Sstran could be made available with a 50 ohm output, it would be a great companion for the new LPAM antenna and would deliver extended coverage for part 15 AM

Steve
Radio Brandy

KNJO Radio, Radio Brandy, Radio Outlaw, Outlaw Radio, XRQK, XRQK FM, AV News Talk, KKTO, KGOE, KDNF, Rave HD. Did time in Los Osos, San Luis Obispo, Thousand Oaks, Simi Valley, The High Desert, Las Vegas, Needles, Victorville, Glendale, Ridgecrest.

50 Ohm Antenna

Hi Steve,

The SSTRAN transmitter does have a mode to work with a low impedance antenna. This is the mode it runs in with the SSTRAN antenna, http://www.sstran.com/pages/sstran_buildant.html. The mode is set by simply setting all 4 inductor selection DIP switches to ON. This bypasses the internal inductors allowing the loading coil to supply the required inductance in a much more efficient manner compared with the small internal inductors.

The actual impedance of a base-loaded antenna is almost completely dependent on the ground resistance, which can range from less than 10 ohms to near 100 ohms in a typical part 15 installation. When the coil is tuned precisely to the antenna, the coil and antenna reactances cancel leaving just the coil loss resistance (maybe 5 - 10 ohms) in series with the ground resistance.

I would expect that your forthcoming 50 ohm antenna will work with the SSTRAN transmitter, and likewise, I would expect that the SSTRAN base-loaded antenna would work with the Panaxis AM-100.

Phil B

SSTRAN Transmitter Low Impedance

Phil that is really good news! I have not had a Sstran around here for sometime. All of ours were given new homes to get some stations off the ground.

The new antenna would be a perfect companion for the Sstran. Preliminary test using a signal generator shows outstanding performance, now we need to test it with a transmitter for our final test and review.

The combination of the new antenna and a Sstran may provide the most bang for the buck, for those who don't need a certified transmitter, but still want decent coverage.

I will have to work a Sstran into the budget at the beginning of the year to finalize the test.

The meltdown could be good for part 15 AM XMTR sales, just based on the 10 fold increase in traffic coming to our part 15 AM site in the last week. Allot of radio people have been shown the door in recent months, Part 15 broadcasting is a good way to keep the green backs coming in.

Surviving The Meltdown

Steve
Radio Brandy

KNJO Radio, Radio Brandy, Radio Outlaw, Outlaw Radio, XRQK, XRQK FM, AV News Talk, KKTO, KGOE, KDNF, Rave HD. Did time in Los Osos, San Luis Obispo, Thousand Oaks, Simi Valley, The High Desert, Las Vegas, Needles, Victorville, Glendale, Ridgecrest.

New AM100 Network

"I just made contact with my engineer after 23 years, I'm sure he will be on this board soon. He thinks we can pull off the recreation of the AM100, the trimmer cap should not stand in our way."

I'm now on this board. It's amazing how many forums I can find Steve on, now that I know his handle.

When I get the time, I would like to dig out the original AM100 I modified nearly a quarter century ago, and build a new one, 21st century style.

I would like to set up a whole network of the AM transmitters in the area I now live in.

We have many unoccupied AM frequencies here.

In my opinion, Steve had the best sounding part15 I have ever heard.

With the Breakaway Broadcast Processor I have on my computer, plus using Zara Radio automation, I think these little AM's will kick major ass!

I know this thread is old.

I know this thread is old. But out of extreme curiosity, what became of this project?? I had a friend many many years ago that had one. It was quite impressive at the time. I remember it having very strong clean audio. Going through the archives brought some memories back. I have a couple of Panaxis FME500 exciters I purchased from Ernie way back in the day. Still working strong. Would be nice to see a similar kit return.

Brian

Up In The Air

"out of extreme curiosity, what became of this project??"

Have not heard anything since that big announcement. I still have my Panaxis AM 100 and Panaxis FM units.

That AM 100 is easy to construct on perfboard and the trimmer cap is replaceable with another type. Extending the frequency range is no big deal either by simply replacing the 4018 with a different divider and crystal.

RFB

Yes, I downloaded the plans.

Yes, I downloaded the plans. I need to sit down and maybe plan an attempt at building one.

Brian

Blast From The Past

This past weekend while finishing up a transmitter rebuild project (a dandy dumpster find!), to break out the ol Panaxis AM-100 unit from the TX History shelf.

The unit, after sitting for years without any power, fired right up and on frequency. So I then proceeded to use the Panaxis AM 100 as an exciter to drive an LPB 25 watt amp with the exciter in the 300% modulation mode.

WoW!! That lil ol Panaxis drove the heck out of that 25 watter with pure clean modulated sine wave peaks and nice rounded off neg. peaks and blasted away all the commercial stations in sound!

Think it's time to un-retire that Panaxis AM 100!

RFB

Percent of Modulation

Never up until now has any modulation level above 125% been known to me.

Even this seemed possibly questionable when 100% modulation would be, by definition, a fully formed modulation envelope combined with a carrier.

Like having a wider frequency response than the width of the allowed channel bandwidth, doesn't so much above 100% exceed the bounds of FCC regulations?

How the......300% ?

Carl Blare

Any New News?

I don't remember how I ran across this topic... maybe I googled "panaxis"... Yeah, I think that's how I found it... by accident.

I remember sending off my $2.00 for a catalog back years ago.
A Classified AD for "Your Own Radio Station" sparked an interest with me for one reason or another... Perhaps because I wasn't satisfied with the range or frequency drift from that little tube transmitter I had built from The Radio Amateurs Handbook.

I remember flipping through the pages of the educational little catalog, then sending in a check for (seems like) $75.00 for my PLL AM transmitter kit.

The instructions were straightforward and quite educational when building the transmitter in stages and reading the description of exactly what function each stage preformed. Pricy, but educational. Support was always a phone call away. So the investment was well worth the price of the kit from both an education and a recreational standpoint.

Has the idea of bringing these kits back been advanced?

I realize this is an old topic, but if the quality of the kit and instructions remain the same, I would be interested in investing for the children and grandchildren ...not to mention the opportunity to relive a few my younger days through their eyes.
Still learning after almost 33 1/3 years.
I specialize in long periods of dead air.
You see, We have these things called turntables. They play vinyl discs called a LP, but I forget to turn them over.
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