H. P. Friedrichs (AC7ZL) Homepage
If Rigs Could Talk:
An Iraqi Veteran Comes to the United States
While I am as enthusiastic about cutting-edge technology as any person, I have a special fondness in my heart for vintage electronic and radio equipment. My reasons vary. In some cases, vintage equipment exhibits the aesthetics of elegant, if outdated, design. Sometimes there is beauty in the attention to detail and care with which the equipment was fabricated. Often, my attraction is rooted in wonder as to the history associated with that gear. Where did it come from? Who might have owned it? I know I'm not alone in asking such questions, because I have met antique and "boat anchor" enthusiasts who will research prior owners of a transmitter or receiver with the same enthusiasm and vigor that they would apply to researching their own genealogy. Ah, but if old rigs could only talk! What might they tell us about historical people, places, and events? Recently, I set out to research and restore a piece of battle-tested communications gear from the first Gulf War, and these questions lingered in my mind. The radio itself is a marvelous piece of engineering, but the equipment's history and how it came into my possession is an interesting tale in its own rite.
The First Gulf War
Iraq's relationship with Kuwait has always been strange, if not strained. While Iraq has never recognized Kuwait's sovereignty, the two countries were none the less allied during the Iran-Iraq war of the 1980's. Kuwait even provided financial resources to fund Iraq's efforts. Unfortunately, this assistance left Iraq in debt to the tune of some 14 billion dollars, a significant source of resentment for Iraq's leader, Saddam Hussein. It was later alleged that Kuwait was engaging in "slant drilling" into Iraqi oil fields, building settlements on Iraqi soil, and devaluing Iraqi oil by exceeding OPEC oil production quotas. Hussein decided that there was justification for a military invasion into Kuwait. The annexation of Kuwait, he reasoned, would resolve these problems, as well as leave Iraq in control of 20% of the world's oil reserves. So, on the 2nd of August, 1990, Iraqi forces swarmed the border into Kuwait.
During their occupation, Iraqi forces are alleged to have terrorized Kuwait's population with acts of torture, rape, and murder. Hospitals were gutted, and key infrastructure elements like desalination plants were destroyed. Communications equipment was gutted, leaving Kuwait disconnected from the rest of the world. Oil facilities were blown up and left in flames. In many cases, anything of value, including items bolted to the floor, was ripped out and transported back into Iraq.
Only later would Hussein realize that his decision to invade Kuwait was a matter of grave miscalculation. After the adoption of a series of impotent United Nations Resolutions, a coalition of 18 countries, headed by the United States, began the execution of a decisive response. On January 17th, the pulverization of Iraqi military forces commenced. Ultimately, more than 1300 aircraft engaged targets dropping 60,000 tons of explosives. In round numbers, 840,000 ground troops deployed and maneuvered 8600 tanks, 15,000 armored vehicles, and 7,000 artillery pieces of various types. Iraq's air force was rendered irrelevant almost overnight. In the days that followed, coalition forces destroyed 3700 Iraqi tanks, 2400 armored vehicles, and 2600 artillery pieces, including 1400 retreating vehicles annihilated on the infamous "highway of death."
Much of Iraq's military hardware was exported to them from other countries, including the AMX-10P, manufactured by the French. Introduced in 1973, the AMX-10P is a tracked, armored, infantry fighting vehicle. A 300 horsepower diesel engine will drive the 16-ton vehicle to speeds up to 40 miles per hour. It is armed with a 20-mm dual-belt-feed automatic cannon, and a 7.62-mm coaxial machine gun. The standard crew consists of 3 persons, with carrying capability for up to 8 passengers.
(AMX photos courtesy of A. Misner and http://www.chars-francais.net)
It is not difficult to imagine a specific AMX-10P and its crew, somewhere in the middle of the melee described earlier, exchanging gunfire with coalition forces. They may have been launching an assault, or perhaps they were attempting to retreat. Either way, by the time the shooting had ceased and the thunder of cluster bombs had receded, the vehicle in question had been reduced to scrap metal. At that point, any sign of life would have been limited to the faint crackle of a VHF transceiver mounted beneath the driver's seat. Bear this image in mind, as it will become relevant in just a moment.
Gulf War II
Following the first Gulf war, the United Nations Security Council issued resolution 687 which declared a formal ceasefire and prescribed to Iraq the terms of peace. Among those conditions was the requirement that various types of weapons systems be dismantled and rendered nonfunctional and that Iraq must allow inspection teams to verify compliance. A decade later, on the 8th of November, 2002, the Security Council unanimously approved resolution 1441, which recognized Iraq's failure to comply with the terms of 687. Resolution 1441 and faulty intelligence about the status of Iraq's remaining WMDs (weapons of mass destruction) led to the formation of a new coalition, one whose purpose it was to disarm Saddam Hussein by force.
On March 20th, 2003, the United States, the United Kingdom, Australia, South Korea, Italy and Poland launched an offensive that smashed Iraq's remaining military and toppled the Saddam Hussein regime forever. WMD's or not, the horrific effects of Saddam's handiwork are felt to this day.
One of the practical considerations of regime change, and one of the real dangers, is that the vacuum formed by the removal of a despot may be filled by something far worse. As we have seen since 2003, managing this vacuum and helping the Iraqi people to transition back to stable autonomy is a daunting and resource-intensive task, one which has demanded the talents and dedication of thousands of our military people.
Meeting Sgt M
Several years back, I wrote and published two books. The first, The Voice of the Crystal, deals with basic radio principles, problem-solving philosophy, and details on the construction of radio components from scratch. Projects include headphones, coils, capacitors, and detectors fabricated from shoe polish tins, bits of wire, a part of a cigarette lighter, and other trashcan flotsam. The second book, Instruments of Amplification, deals with the concept of amplification. It features projects ranging from electromechanical amplifiers built from coils and carbon rods to homebrew vacuum tubes and experimental homebrew transistors. Many thousands of these books are now in circulation, and as a result of this modest success, I have had the good fortune to meet and correspond with people from around the world.
I first met Sgt M under these circumstances. He contacted me with some book-related questions, and we began a pleasant dialog. Sgt M is an intrinsically nice fellow, more than reason enough to engage him, but it turns out that his enthusiasm for electronics and radio, in many ways, parallels my own. Needless to say, we became friends, and our correspondence continues to this day.
At one point, I received an email in which he described an opportunity he'd had to visit one of Hussein's junkyards--- the place where damaged and destroyed military hardware, like the AMX-10P described earlier, was taken to be scavenged for parts. Sgt M later described his adventure this way:
"I was working primarily out of an LSA (Logistical Supply Area) North of Baghdad Iraq. My bread and butter for this tour in Iraq was implementing and upgrading various types of communication Systems theater-wide. At least once a month, I would thumb a ride via rotary wing aircraft to establish and maintain individual Units' communication systems in remote areas. All of the Units that I traveled to fell under our command in theater and most were National Guard / Reserve components that did not have their own direct support personnel.
It was on a short routine trip to Al Taji to check up on and hopefully increase the bandwidth for one of our Companies that I came across these radios. I enjoyed trips to Taji for the simple fact that I could always somehow improve their connectivity in one way or another. The payback for me was a very nice trailer to sleep in and a bit of time in the evening to my self for how ever long I stayed (this was a hot commodity in my book).
It was one late afternoon that I ran into a Company Commander from one of the Postal Units on Al Taji who heard I was in the area and had a couple of very important questions. He wanted to know how to use a PRC-77 radio and where to find batteries for them. After talking some time and explaining to him the best I could without actually having a radio to show him, he brought me to his make-shift plywood office. In his office, stacked very neatly up against one of his self-proclaimed architectural master pieces he called "a wall," there had to have been over 20 PRC-77s, all in great shape. I was very excited hoping that with my information about getting them up and running I would in return receive at least one of these radios for myself. This was not the case, but what he said he would do for me is take me to an old gulf war bone yard full of battle-scarred depleted uranium-saturated tanks, boats, and a wide variety of fighting and troop transporting vehicles. Of course I was disappointed not getting a radio or two out of the deal but the trip did sound interesting and in any case relaxing. Needless to say I think the crusty old Reserve Postal Unit Commander may have lost a couple of DSN phone lines before the week was out.
We decided on heading out the following morning right after sunrise with a couple of field grade officers joining us that had not yet made it out there. The trip did not take very long it was maybe a couple miles from the Unit that I was working on. It was a very impressive sight, row after row of disabled vehicles of all shapes and sizes. We drove up and down the rows as I listened to the old men speculate what type of vehicle we where looking at and what country would have brought it over here. Finally I was given a chance to get out and really explore the insides of this things, most of which where in good shape on the inside they where just missing every nut and bolt that wasn't destroyed and may have been worth something. It was during my exploration of a very strange vehicle that I ran across something that caught my eye. This track vehicle had a rear end shaped like a US Army 113 APC (Armored Personnel Carrier) and a barrel attached that looked a little smaller then our Bradley Fighting Machines 25MM. I noticed some old radio mounts still bolted down on a shelf inside and saw where they had been cannibalized at one time probably from some one just like my self. I started to dig around the driver's area looking for cables or anything else that might lead to some sort of treasure. It was then that something caught my eye that was buried under a thick silky layer of Iraqi dust, a radio knob. The radio I uncovered was bolted directly under the driver's seat and the way it came out seemed to me like it was an "Oh Sh*t" radio. What I mean by this is it was capable of being removed from the vehicle very quickly before they had to abandon it and still maintain some sort of communications to the mother ship. I wish I knew what make and model those vehicles where that I pulled the radios from. The only really big clue that I had was everything inside was written in French, I suppose that's about as detailed as I can get. I did a little research online and discovered a track vehicle that looked pretty close to what the radios where in, it is called an AMX-10P."
I studied the photos Sgt M sent with great interest. Imagine my surprise when he declared his intent to send me one of his treasures! "My only condition," he said, "is that if you figure out how to get it working, that you'll help me with mine." Sgt M filled out the necessary paperwork to have the radios declared as "war trophies," and they were shipped to North Carolina. Not long after that, a large box appeared at my home in Arizona. I opened it with excitement, and even my wife stood nearby to see what would emerge from carefully padded box. The mystery transceiver had arrived!
A First Glance
Sgt M's package contained two assemblies. The first was a radio set composed of an olive-green radio chassis, a snap-on power supply/accessory unit of some type, and a 15-watt RF linear amp attached to the side of the radio like a sidecar. The second assembly was a green aluminum brick with rows of BNC connectors on opposite ends. This appeared to be some kind of bandpass filter.
All of the hardware was muddy, and peppered with gobs of what appeared to be hardened cement. Since this was, after all, combat military hardware, I thought it reasonable to assume that it would tolerate some moisture. I took the equipment out back and attacked it with the garden hose and a nylon brush. The "cement," it turns out, was sunbaked clay, not unlike the caliche found here in the Southwest. All of the equipment cleaned up nicely.
The transceiver, as received, was composed of three subassemblies. The first, the transceiver itself (part number ER95B), a box-like accessory module (part number BJ231A ) which fastens to the bottom of the receiver, and an RF power amplifier module (part number AM215A ) which was bolted to the side of the transceiver in "sidecar" fashion.
The transceiver is fitted with all of the operating controls and connectors for a headset and antennas. The controls include two tuning knobs, one of which sets the MHz portion of the desired frequency, the other which sets the KHz portion. Frequency is displayed mechanically through two tiny, round, windows. Selectable frequencies span the range of 26.000 MHz to 71.950 MHz, with a 50 KHz spacing. This means that from end to end, the system provides 920 discrete channels. Since this is a fairly extensive range of frequencies, the designers broke up this span into two bands, which are selectable with a front panel switch.
Additional controls include the obvious, a volume control, a squelch control, and a multi-position mode switch. The mode switch turns the radio on, places it under local or remote control, and allows activation or deactivation of the squelch.
The antenna terminals, which include a BNC as well as a threaded well in which to secure a whip antenna, are located towards the left side of the control panel. At the right of the panel are two circular connectors, identified by Sgt M as "U-79" connectors. (Note: The U-79 is a panel mount connector. The mating connector is called a U-77.) Obviously, these are connection points for the operator's headset.
The accessory module is held into place at the bottom of the transceiver with two spring-loaded suitcase-style snaps, and links to the transceiver internally with a captive DB-25 connector. The outside of the accessory module almost bristles with military-style circular connectors. The side of the module features connectors for power, remote control, for control of the external RF amp, and for interface to what I presume would be an antenna tuner/matching unit. In addition, there are several connectors at the bottom of the module for test and other unknown purposes.
The outboard RF amplifier was attached to the left side of the transceiver. A short length of coax fed the amp from the BNC connector on the face of the transceiver. At the rear of the amp is a short but fat pigtail that links to the accessory module. This must be the conduit through which power and control signals are applied to the amp.
Two interesting contradictions are inherent in the radio I've just described. First, while the radio is clearly of French origin, and the connectors on the accessory module are labeled in French, the front panel controls are labeled in English. Second, while Sgt M had salvaged this radio from a tracked vehicle, its overall design said "manpack" to me. After all, the radio clearly supports the use of a whip, and I could easily envision the accessory module removed and replaced with a similar box filled with batteries.
Dead Ends and Discoveries
The nameplate indicated that the radio had been manufactured by Thomson CSF. I Googled "Thomson," and discovered that they are now doing business under the name "Thales." I found a phone number for the company division in the United States. I spoke with an engineer and inquired how I might be able to get my hands on schematics or service information. He was friendly, though unable to help me. He indicated that the documents pertaining to the radio were controlled by Thales in France. He ended our conversation when he made a peculiar remark, wishing me "luck" in dealing with the French. Hmm.
Next, I composed a letter to Thales in France. I don't speak French, so I composed the letter in English and then used one of the online translation services to convert the message. It was weeks before I heard anything from them, and when I finally did, they simply remarked that the radio was "obsolete" and that they could not help me.
A Google search of "ER-95" yielded little, so I decided to change gears. Since the radio was French, it occurred to me that I should try a search using French words to search with. I initiated searches using words like "transmetteur" (transmitter) "récepteur" (receiver) and "militaires" (military). This path eventually led me to the web site of a French surplus dealer. I scanned through the photos on the web page with the hope that I might find an example of my radio. I eventually stumbled on the image of a set that was identical to mine, but for minor differences associated with the shape of the tuning knobs. The caption read: "TR-PP-13."
Armed with the discovery that the transceiver was known by nomenclature other than ER-95, I Googled "TR-PP-13." The resulting links led me to a goldmine of information in the form of an article entitled, The French/Italian TR-PP-13/RV-3 (ER-95A) VHF FM Radio. This article, authored by J. Feyssac and M. McCabe, was featured in the June 2004 issue of the Vintage and Military Amateur Radio Society newsletter. According to Feyssac and McCabe, most of the NATO armies in the mid 1950's made use of the PRC-10 family of military radios. Military demands for improvements and the growing proliferation of transistors led to the development of the PRC-25 in 1961, and eventually, the PRC-77. France decided not to adopt the PRC-77, but rather, design her own system. This decision led directly to the development of the TR-PP-13, manufactured by Thomson CSF, and the later production of the RV-3, an Italian variant manufactured under license by Elmer.
The VMARS article goes into considerable detail about the design and specifications of the TR-PP-13, including a description of the how the internal frequency synthesis is accomplished. In short, I can say that the receiver is a single-conversion superhet with sensitivity to 0.5uV (18 dB s/n). Audio output is 5 mW. The transmitter (without the outboard RF amplifier) produces 1.5 watts (a 5 to 15 km range). The transceiver contains 46 transistors, and weighs in around 25 pounds.
As I had initially suspected, the TR-PP-13 was deployed in at least three different configurations...a manpack, a jeep radio, and a "tank" version. The tank version, system TR-VP-213 (Italian RV-4/213/V,) consists of the radio, the BA-301 power supply (Thomson calls this a BJ231A) and the RF-AM215 amplifier. This is consistent with the hardware that Sgt M sent to me.
Getting the Radio Working
Despite the excellent article by Feyssac and McCabe, I was still without schematics, and still unable to power up the radio. I decided that a look inside might offer some clues. I unsnapped the accessory module from the bottom of the radio, and then I removed the metric Allen-head bolts which secured the radio into its case.
Predictably, the interior exhibits high quality construction. Most of the electronics associated with the radio is housed in small, silver-plated metal modules that plug into to the set. Wiring harnesses are neat, short, tight, bundles. Of course, while this type of construction makes for a rugged set that is easy to service in the field, it makes reverse engineering exceptionally difficult.
Starting with a connector labeled "Alim 24" mounted to the side of the accessory box, I used my ohmmeter to trace some of the wiring. I eventually decided that, on the basis of these measurements, the radio case was a negative ground, and that three pins on the power connector must receive power. I removed the RF amp and its cabling from the radio (figuring I'd work on that part later). Using alligator leads, I rigged up a current-limited bench supply to provide 24 volts and switched on the radio. There was evidence of a current draw. I turned the radio off.
I was curious about a knurled knob on the face of the transceiver. It was embossed with a curly symbol, reminiscent of a lamp filament. I presumed it might have something to do with a pilot or dial light. I unscrewed the knob, and found an empty lamp socket beneath it. I replaced the bulb and turned the radio back on. The circular windows in which the frequency is displayed lit up. So far, so good.
Next, I had to try to figure out how the headset connector was wired. Unfortunately, the wiring can't be followed from the inside of the radio, and without schematics, my only recourse was trial and error. I powered up the radio and began probing the connector pins with the terminals of a 2000-ohm high-impedance headphone. My logic was that this might help me locate the audio output pins, and even if I crossed something that I should not, momentary contact was not liable to damage anything. I turned the radio on, turned the volume all the way up, and the squelch all the way down. Sure enough, as soon as I touched pins "A" and "B" I heard the hiss associated with an un-squelched FM receiver. I continued probing the connector, and discovered that when terminals "F" and "H" were shunted, a relay inside the radio clicked and the audio was silenced. I was sure that I had found the PTT (push-to-talk) terminals. From that point on, I connected the radio to my 50 ohm dummy load to protect the RF finals and to make sure that I would not unintentionally radiate signals.
A few days later, I discovered Brooke Clarke's website. Posted there, he shows the pinout for the U-79 connector as deployed on PRC family radios. I compared this information to the wiring I had derived through my experimentation, and found that it matched. This suggested to me that the microphone terminals must be pins "C" and "E." I also learned that the PRC family radios utilized carbon microphones, which implied that this radio would require a carbon mike, as well.
I rummaged through my junk box and retrieved an old, standard, telephone handset. These contain a dynamic speaker and a carbon microphone. I gutted the handset and drilled a hole on the handle, near the earpiece, in which to install a momentary-contact PTT switch. I rewired whole thing, fabricated a nice cable, and then terminated that cable with a U-77 connector purchased from Fair Radio Sales. Before finalizing assembly, I gave the handset two or three coats of military-olive-green paint so that it would match the radio.
I made duplicates of my homebrew handset and power cabling, and sent them off with a power supply to Sgt M, along with details of what I'd learned. Last I'd heard, his transceiver fired up and worked fine.
And the RF Amp?
The short story on the RF amplifier is this: Try as I might, I could not get the amplifier to key up. I probed the connector that feeds the amp, but failed to identify any of the signals. I opened the amplifier to study its innards, but nothing there suggested what I must do to get it working. My guess is that something must be strapped on one of the radio's other connectors to enable the operation of the RF power amplifier. Given the relative complexity of the hardware I'm dealing with, combined with the nature of its construction, it is unlikely that I'll get the amp functioning without additional technical documentation. If any of my readers should have an idea as to where I might obtain schematics for this radio, I would be very interested in hearing about it.
So What's the Point?
As far as I can tell, this rig works great. The receiver seems sensitive, and the audio quality of received signals seems pretty good. Even with a makeshift antenna, I can pick up audio from television channels 2 (59.75 MHz) and 4 (71.75 MHz). I have transmitted into my dummy load numerous times, and when my handheld scanner is brought near, the audio quality of the signal emitted by the radio is remarkably clear and crisp. It might be fun to rig up an antenna and try out this radio on the 6 meter band (50 MHz to 54 MHz). The 50 KHz channel resolution and 20 KHz channel width limits one's agility, but looking at the band plan, there are several places I could probably operate. Sgt M send me an email wondering if these radios could be utilized with PSK-31. I don't see why not, assuming a suitable interface was constructed.
A few months back, I penned an article in which I described my restoration of an old BC-348. By far, most readers applauded my efforts, though at least one asked why I would bother. He said, "It's just an old obsolete radio with a lot of hours of work to make it function worse that a $20 Chinese SW radio. So why would we do this?" No doubt this person and others like him would ask the same question about my TR-VP-213. After all, it too is old, obsolete, and of limited value on the ham bands.
The question is a fair one, though I submit that it is only likely to be asked by those who do not understand that a journey can be more important than the destination. As I reflect on my efforts to research and get Sgt M's radio functional, I note that I have learned some history, and some politics. I've corresponded with military radio enthusiasts in the UK, and I've learned a few words of French. I learned some new things about military radios, their ancestry, operation, design, and construction. Most importantly, a mutual appreciation of radio and electronics created the opportunity for, and solidified, my friendship with a serviceman on the opposite side of the globe. If these benefits are not representative of the best face of ham radio, I'm sure I don't know what is.
As for the radio and its history, one can only imagine where it has been and what it has seen in its travels-- from France to the deserts of Iraq... from the deserts of Iraq to brutal combat....from combat to a peaceful boneyard... from the boneyard to North Carolina and then finally to Tucson, Arizona in the United States of America. Oh, if only rigs could talk!
A Brief Editorial Comment
The U.S.A.'s actions in Iraq and elsewhere around the world have been the source of friction between our nation and others, and between the members of our increasingly polarized population. The intent of this editorial is not to advocate any particular position, but simply to suggest that you reflect, from time to time, on the extraordinary sacrifices made by the members of our Army, Navy, Air Force, Marines, and Coast Guard.
If you fly a flag at home or display a "Support the Troops" sticker on your bumper, that's well and good, but I would urge you to take the next step. There are thousands of servicemen overseas who would appreciate a friendly letter from someone back home. Better yet, consider sending a "care" package filled with socks, candy, instant beverage mixes, magazines or similar items. What better way to say "Thank you?"
"What should I send?" you ask. "To whom do I send it?" Start by visiting www.anysoldier.com
Web Article Update: New Information and New Functionality!
After preparing and posting the article above, I continued tinkering with the radio in an effort to get the RF amp running. The breakthrough finally came after I was able to establish contact with Murray McCabe, one of the authors of the VMARS article I described earlier. Murray has accumulated considerable information on the TR-VP-13, including schematics and other critical information. This data is available on CDROM for a very reasonable charge, and I was more than happy to purchase a copy. With this new information, I revised the power harness I had created earlier, and then created a simple shunt or "jumper" for one of the accessory connectors to enable full RF power when I want it. Let me summarize what needs to be done here.
To build the appropriate power cable, one needs a military circular connector with a part number of PT06A-10-6S (or an equivalent.) Cut, strip, and tin six wires for the power harness, and solder one to each of the six connector terminals. The three wires from pins (B), (C), and (D) are joined together and become the positive (+) 24-volt connection to the radio. The three wires from pins (A), (E), and (F) are joined together and become the negative (-) 24-volt connection to the radio. The power harness you've created is attached to the connector labeled "ALIM 24 V." I no longer connect any wiring to the radio housing.
To enable the RF amplifer, one needs to connect pin (E) to pin (G) on the connector marked "TELECOM." For me, this was initially problematic as I was unable to find a mating plug for that connector. Allow me to explain:
At first glance, it appears that the "TELECOM," "ACCORD ANT" and "AMPLI HF" connectors are all the same-- they are, in terms of their outer shells. Where they differ is in a feature called "keying." The pin array in each one has been "keyed" differently, that is to say, the pin set in each connector has been rotated to a different angle. This prevents the cables from being attached to the wrong connector, even though they may share similar shells.
Digging through my junkbox, I was able to find several connectors that would mate with the "ACCORD ANT." These were plugs with the part number PT06A-12-8P(SR). I was never able to find a plug that would mate with the "TELECOM" connector. I guess the connector keying associated with the "TELECOM" port must be one of the more rare variants.
To work around this, I fashioned a jumper composed of an inch of wire with a gold connector pin soldered on each end. The jumper was installed between pins (E) and (G) on the "TELECOM" connector. To protect the jumper, I took a PT06A-12-8P and drilled out its center, leaving only the hollow shell. This will fit the TELECOM connector and acts as a tough cover for the jumper.
I may be stating the obvious, but here are a few additional points to keep in mind: The TR-VP-13 must be connected to the amplifier with a BNC patch cord running between the front of the radio and the front of the amplifier. A 50-ohm antenna is attached to the BNC connector at the rear of the amplifier. Also, at the rear of the amplifier, is a short, thick, cable that links the amp to the connector on the radio marked "AMPLI HF." This cable must be in place for the amplifier to function. Finally, The toggle switch on the front of the amplifier allows you to select the transmit power level.
Useful and Interesting Links
I asked Charlie, my assistant, to prepare a brief list of URLs that might be of interest to those seeking additional information on the topic above. This is what he came up with:
Document Revision 1, xx/xx/2007
Document Revision 2, 07/04/2007
Document Revision 3, 10/31/2007