CB World Informer October 1996 Issue EchoMax 2000 Review

This is truly is a new product. Echo mics aren’t new, but digital echo for CB is new. Those of you who detest echo mics please don’t skip this article. I know the majority of echo users are out to annoy the world, but digital echo can be an enhancement rather than a detraction. After all, digital delay, echo, reverb and slapback echo are used in the recording industry as well as in surround sound reproduction.

The first thing I spotted was the pink label on the outside of the box. FREE STEREO HEADPHONES. I thought it was only an unrelated promotional gimmick. After noticing a phone jack on the rear panel of the mic next to a small shaft labeled EAR, I checked the instruction sheet to confirm that the jack is for monitoring yourself with headphones. No need for talkback here. Talkback is almost useless with a desk mic anyway. Most operators want to talk a foot or two from the mic and to do that the mic must be tuned up to be more sensitive causing feedback when talkback is used.


Complete documentation is included. It covers maintenance including cleaning the windscreen, features, controls and their settings, specifications, dimensions and even a schematic. I’ve never seen an echo mic with a schematic before, but Astatic traditionally supplied schematics for their amplified mics. With the latest trend of manufacturers supplying less information to their customers it’s a pleasant surprise to see Astatic continue their old tradition.

Here’s a list and descriptions of the major features incorporated in this mic:

Echo: This is an effect that is familiar to most people. A word spoken into the mic will repeat and decrease in volume until it fades away. The delay time between each echo is set with the Digital Delay control from a short reverb to a long repeat echo of close to one second. You could easily speak five quick words before the echo repeats itself.

Slapback Echo: Slapback echo works exactly as Echo but only repeats once. A short delay adds fullness to your voice, almost like two people speaking at the same time. A touch of this effect does make your audio sound full on sideband.


ETS stands for End of Transmission Signal, Commonly known as “Roger Beep.” There are two selectable tones. One is a single tone and the other is a multiple tone (three different quick tones). The tones are generated digitally and are easy on the ears, or should I say nerves.Headphone Jack: This will drive a walkman type stereo headphone set or an amplified speaker. It has a high quality output and comes from the same amplifier stage that is feed into the radio. So the sound you hear is what’s going into the radio.

To the left, Figure 1, is a top view that will help you better visualize the controls as they’re described, and following are descriptions of these controls and the effect they have per the manufacturer’s instructions and my experience.

Mic Gain: The Mic Gain is a slide control that sets the level into the digital circuitry. This control should be adjusted so that the level indicated on the VU meter doesn’t exceed “+3” on voice peaks. This meter is quite accurate. Distortion in the echo started at +3 of VU meter. The setting of this control will vary depending on how far away from the mic you speak.

Digital Delay: The Digital Delay control adjusts I the delay time of the Echo and Slapback echo effect. Setting the control to the center position turns off the echo effects. Turning the control counterclockwise activates the Echo effect and sets the echo delay time.

Turning the control clockwise activates the Slapback echo effect and sets the Slapback echo delay time. In either case, turning the control towards MAX increases the delay time.

Effects Gain: The Effects gain control adjusts the volume of the Echo and Slapback echo effects. Setting this control completely counterclockwise will act the same as turning off the effects. With this control set completely clockwise, the volume of Slapback and Echo repeat will be at maximum and sound as loud as the original sound picked up by the mic. At MAX the echo the mic tested repeated approximately 10 times. Around nine seconds.

ETS ON/OFF: This push button controls the ETS (Roger Beep) and on is in the out position.

ETS Single/Multi: This push button selects the single or multi tone ETS. Single is in the out position. Master Gain Control: This control is labeled GAIN and is located on the rear panel of the microphone base near the gooseneck. Use this control to set the overall level of the mic. This control is set after the mic gain is adjusted as described above.

Headphone Volume Control: This is also on the rear panel of the mic. Located next to the ear jack it is used to adjust the headphone or amplified speaker volume. The use of headphones will drain the battery more quickly. Astatic offers a wall transformer which eliminates that problem.

This mic is of heavy steal construction with four soft rubber feet to keep it from sliding around. The base is black with gold lettering and trim. The digital control knobs are black with red inserts. The ETS buttons are red. The Mic Gain graphic display and Digital Delay area are blue with gold trim. The PTT and Lock bars are blue. The gooseneck is a black flexible type. The nameplate on the front proudly displays “ASTATIC made in U.S.A.” in gold. The top panel is a tough laminated plastic label that will resist scratches much better than silk screen painted surfaces. Old time CB veteran’s may remember CPI (Communications Power Inc.) used these on the face of all their products including the CPI 2000 base radio. Many of these radios are still around and many of the face plate labels still look new on the 15+ year old classics.

The 9 volt battery can be changed by removing one screw from the rear panel. The instructions recommend the use of an alkaline battery, but I would say it’s required and not an option. Powering the mic with a 9 volt lithium battery (Radio Shack # 23-665) should increase battery life 5 times and only cost 3 times the price of its alkaline counterpart. Ant the shelf life of a lithium battery is about 10 years. If you choose to eliminate the battery its compartment cover has a small hole for the wire of the optional wall transformer.

A look inside the mic and the quality engineering and workmanship is immediately evident. The circuit board is computer generated and glass epoxy not the phenolic boards used in most other mics. The meter and microphone element are terminated with connectors so when the cover is removed they can be unplugged and the cover can be completely detached from the main body of the mic. The push to talk and lock bar are rugged and designed in such a way that even pressure is applied to the PTT switch. No switch failures or scratchy transmissions due to side pressure from poor mechanical designs. The switch should last a long time in this mic.

Looking at the schematic I noticed two amplifier stages dedicated to audio tailoring. This is how they got the sound of the D104 using a electret condenser mic element. In my opinion, the mic sounds better than a D104. It has more low end audio giving it a deeper tone while maintaining the high tone response that the D104 is famous for. On the nest page is a copy of the schematic. Even someone that doesn’t understand it can see that there is a lot of electronic in this unit.


Sorry for the poor quality, this is a copy of a copy. The original is no longer made available.

CBWI©BCB Has 2 EchoMax 2000 in stock and are available to CB World Informer subscribers for $129.95 ea.To Order Call 1 (800) 473-9708.Channel Board For Cobra 146GTL & Uniden PC-122XLThe Cobra 146GTL and Uniden PC- 122XL are low cost AM/S SB radios using a gPD2824 PLL chip. The Uniden PC-122XL is the same radio as the PC-122. They changed to the XL series when they went to the Cobra look front panels. Uniden also made the PRO-810e, a base radio with the same board as the 122. When this chassis initially came out there was no known way to add extras.

This was viewed as just another challenge for the CB hackers and after a short while there were two methods of expanding coverage.One uses two crystals that are switched into the tripler coil and this yields 40 extras above and below the center off position is regular 40, but it created a problem on sideband. This scheme rendered the clarifier inoperative in the expanded positions. A wire from the clarifier control to the expander kit was added to get some clarifier range but it was limited and all three modes had three different center slots.

These kits also work on the Cobra 29-GTL and Uniden PC-76. These radios being AM only, work fine and these kits are the preferred method of expansion.The other kit doesn’t use crystals. It uses two ICs that generate a signal for the tripler coil in the PLL circuit. The clarifier works the same in all positions of the expansion switch. This makes for ease of operation. The only drawback is the total channel coverage is reduced. It doesn’t yield any lower frequencies but it does make the radio cover up to 28.045 Mhz.

Looking at the schematic in the digital delay control area, it looks as if one might be able to increase the delay by playing with the values of R16 and R17. Playing with the values of R47 and R48 would increase the echo gain, but I’m sure that changing any values will result in deterioration of sound quality.On the air results were incredible. Nobody had heard anything like this before. I must admit, I went overboard with the effects and enjoyed it too.

Usually I don’t go in for this type of stuff, but with the flawless repeat echo it’s too tempting to show it off. For my taste I found that setting the Digital Delay to the first line inside the Slapback effect range and the Effects Gain at 7 on sideband gave a fuller effect without a hollow sound. On AM I found increasing these setting slightly gave a fuller sound to my audio.

Playing with the headphones on, I found that setting the Mic Gain to 5 and the Effects gain to 10 I had a reverse echo. What I mean by that is that the echo was louder that the spoken word. This is a unique and interesting effect not mentioned in the instructions. I’m sure there are other effects that can be created with the infinite amount of control this mic offers.

I did notice two minor things. One is inconsequential actually. Using the headphones with the Mic Gain very low some digital noise was detected. This was extremely low and probably should be expected. Anyway this computer noise was not transmitted over the air and probably wouldn’t have been notice except I was listening for background noise specifically. The other is that on some radios the ETS won’t work.

When .the mic is un-keyed the mic drops transmit momentarily before the beep. Some radios have a half second delay before they transmit audio from the time the mic is keyed. This momentary drop of transmit causes some radios to miss the beep tones. This isn’t unique to this mic. The very popular Sadelta Echo Master Plus has the same problem. It only happens on a few models and is easily corrected. A 10 W capacitor on the transmit line in the radio or mic will give enough delay on the transmit line so that momentary drop out isn’t detected by the radio.

The mic cord is terminated with a RJ-45 type connector like those used on telephone equipment and the new ham radio gear. This makes it possible for the end user to change the mic cord if it goes bad. It also allows you to have multiple mic cords pre-wired for all you favorite radios in your closet. Want to run a different radio, just unplug the mic cord from the back of the mic and replace it with one wired for the radio of your choice.

Here’s a list of Astatic options and replacement parts:
42577-00-00 Windscreen
43838-00-00 Detachable Cable
EM-KIT Wall Transformer And Headphone Set


Warning: The modification of the radio in the U.S. voids the FCC type acceptance and makes the equipment illegal!The installation of the circuit board is easy. The leads should be as short as possible. Locate the PC board as close to the 2824 PLL chip as possible. Either a SPDT center of toggle switch or a three position rotary switch can be used. If you buy a kit, it comes with the toggle switch mounted to the PC board. It can be removed or used to secure the board and switch in one step.

If you choose to build the PC board you can use a multipurpose PC board such as Radio Shack #276-150 or #276-159. Position all the components as close together as possible. Hand wire all connections using short wires. Mount the board securely and be sure that nothing metallic comes in contact with it including the speaker on bottom cover.

Once the PC board is installed and wired to the switch, four short wires need to be connected to the PLL circuit. First run a wire from the connection with the ground symbol on the expansion PC board to the can of L15. Next connect the lifted side of C67 to the (OUT) connection of the expansion board. Connect IC2 pin 10 to the expansion board connection marked (IN). Then connect IC2 pin 11 to the expansion board connection marked (+5 VOLTS).

To insure complete VCO coverage solder a 27pf capacitor across C72 on the back side of the radio circuit board. Make sure to lay it down flat and keep the leads short. Then double check your work looking for solder bridges and correct connections.


Next is the alignment procedure. Connect a watt meter, frequency counter and dummy load to the radio.1) Put the radio in the AM mode on channel 1 with the expansion switch in the normal position and transmit. You should read 26.965 on the frequency counter. If the radio doesn’t transmit, there may be a wiring mistake somewhere or the VCO may need adjustment. Adding the capacitor across C72 does change the adjustment slightly, but not usually enough to loss channel 1. If everything looks OK then melt the wax in L38 and adjust it slowly in either direction no more than 3/4 of a turn. You should now transmit on channel 1.

2) Put the expansion switch in one of the upper channel selections. and adjust L13 until you read either 27.285 or 27.605 on the frequency counter.

3) Put the expansion switch in the opposite expanded position and you should read the other frequency listed above. You should read 27.285 in one position and 27.605 in the other position. If not, tweak L13 a little until you do.

4) Check to see that you still read 26.965 in the normal position.

5) Switch to the position that yields 27.605 and switch the channel selector to channel 40. The counter should read 28.045. If it doesn’t, melt the wax in L38 and slowly adjust it until you read the 28.045 on your counter.

6) Go back to normal channel I and insure that you read 26.965 on the counter.

If everything went well you have a radio that goes up to 28.045. Of coarse we know you will only receive these frequencies and never transmit above 27.405. Remember 28.000 is the beginning of 10 Meters.

I’m told for the Ham operators out there, moving the wire on the expander from pin 8 to pin 9 on the 7493 IC along with adjusting L13 and L38 will give you coverage in the novice portion.

Well, this article was supplied for information purposes and I hope you enjoyed it. Even if you don’t tinker with radio equipment it’s always good to be aware of what’s available. Have fun! ©CBWI


Kenwood TS-45OS-AT Complete coverage 10OKhz – 3OMhz like new with MC-60 desk mic $995.00. Call: SOLD 

New For Sale Section…At No Charge!

If you have any items for sale, drop us a line or FAX it. Please include the mailing address or phone number you wish to have published for contact. If you use a phone number please include the State and time zone you live in along with the times to call. ©CBWI

Editor’s Note

Some of you may think the information presented in this publication is too technical and might be over your head. The intent, as our name implies, is to inform everyone. The material may go into more detail than some of you need but others may have a better technical understanding and have a use for this information. This includes the product reviews which are the old fashioned type where the good, not so good and bad points of a product are exposed, from both an end user and technical point of view. One thing you won’t find in this publication is misinformation to appease advertisers. Goal #1 is to inform the readers with the truth. Anything less wouldn’t be worth while writing or reading. Only honesty serves public and industry interests best. If this is correct CB World Informer circulation will grow and that too will benefit us all. The more information s lied the easier it is for you the reader to make up your own mind. If the technical information was eliminated, it would only water down this publication. Absorb what you understand and save your issues for future reference. They will come in handy as articles will refer to previously covered information from time to time.

It may be a silly dream, but I hope to see the day we send out the first full color glossy covered Issue of CB World Informer magazine. A larger, more refined high resolution photos and print quality version of the newsletter with a wider spectrum of complete coverage is what I have in mind. I hope it will be, as our slogan adopted in 1990 stated, “WHERE THE CITIZENS BAND.” The holiday season is just around the comer, consider giving a CB World Informer subscription as gift for your radio friends.

My thanks go out to all of you that are spreading the news about this new publication. It has helped with increased subscriptions. Keep up the good work. Word of mouth does work best.

If you have any questions you would like answered, suggestions on what you would like covered or reviewed send us a post card or fax. I can’t guaranty that we’ll do every one but we’ll do what space and time permit. ©CBWI

Did You Know?

On the RCI 2950 in memory channel mode there is a way to transfer the memory channel frequency into the manual mode. Many of you know that when on a memory channel you can’t change the frequency with the cursor and up/down buttons. This can only be done in the manual mode. Once you press the manual button the radio changes from that memory frequency to the last frequency used in the manual mode. This is inconvenient if you only want to move 5 or 1OKhz from where you were. Well, it’s not listed in the operators manual, but all you need do is press scan before manual and this will transfer the memory frequency into manual and operate the radio as usual.

If you have a friend with a RCI 2950, 2970, 2980, or 2990 pass the information on and tell them where you got it. ©CBWI

Increasing Interest In CB Rumored

Rumor of interest in the hobby being on the rise again from CB manufacturers was confirmed as I read a feature article in the November issue of Popular Communications titled Class D CB: The Service That Technology Forgot by Bill Pasternak, WA61TF. In brief, the article covered how other radio services have changed technologically to better utilize the available spectrum and minimize crowding. Meanwhile CB hasn’t seen any improvements since the inception of Single Sideband. Bill points out his monitoring has verified that the need for improved technology is essential “because 11 Meter CB is growing again.”

Evidently something is happening. How long it will last? It could be short lived, but I don’t think so. With new CB products available and on the horizon, it’s obvious the big money’s thinking long term. Radio Shack has made big changes in this area. By increasing their CB product line, offering products apparently made by well known CB manufacturers, they’re getting serious. When the amateur no code license proposal was passed it didn’t take, them long to offer 2Meter and 44OMhz equipment. And they have increased the number of products in this area. They even carry a 70 foot crank-up tower by Hy-Gain! Believe me, they don’t focus in areas of dying interest. Thumbing through their 1997 catalog looking at and reading about the new CB products it appears that Radio Shack may have changed their philosophy about CB. They are now offering a AM/SSB mobile again. It even has a 5 digit frequency display. How about CB mobile antennas with open air and oil filled coils that handle 1000 Watts. Is this the Shack we all know? They always seemed to have an extreme policy of not carrying products that promoted or implied the promotion of illegal activity. It may not be as big of a change as it appears, but it is an easing of policy in this area. I’ve never been able to say this before, but I’m curious about some of their new products and you will see product review of Radio Shack products in future issues.

Also the following article can be considered a forth indicator to add credence to the rumor. ©CBWI

New Products

Not only are there two new products to report, but they’re from a relatively new name in the industry, Cherokee Electronics Trademarked by Wireless Marketing Corp. I first heard of Cherokee Electronics less than a year ago when a customer came in to show me the new Cherokee AH-27 handheld CB. It was the smallest hand held CB I’d ever seen. It resembled a 2-meter handie-talkie in size, shape and quality. The AH-27 fits the need of today’s market with its small size and advanced features. It has 5 memory channels, 15 segment S/RF meter, dual watch, scanning and much, much more. Needless to say, the customer as extremely happy with his new purchase and suggested that I carry the product, but at the time I was pondering closing the retail store so I didn’t.

Now they have two new products on the way and are displayed on the next page. The first is the CBS-1000 AM/SSB Base Station CB. From the photo it looks like a variation of the Cobra 2010. When I called Wireless Marketing they insured that it’s not the same chassis as the 2010.

Here are the features listed on their CBS-1000 marketing flier:

40 Channels AM/USB/LSB

LCD “Information Center” Incl. Freq. Display

 4 Watt AM, 12 Watt SSB Output

10 NOAA Weather Channels

Fine/Coarse Clarifier Controls

Mic Gain, RF Gain & Squelch Controls

Dual Measurement Meters

SWR Calibration

Selectable Noise Blanker & ANL

5 Preset Memory Locations

Auto Channel & Memory Scan 

Power Option: 11OV AC or 13.8V DC

The county of origin is listed as the Philippines. We’ve seen some good Uniden stuff from the Philippines. The flier also states many additional features. We all like additional features … This looks like a product that deserves a close look when it arrives.

The second is even more exciting, the model AH-100 40 channel AM/SSB Handheld CB. Yes, a SSB walkie talkie. This is one that I’ve been waiting for a long time. Back in the 70’s midland announced a SSB walkie talkie, but I don’t know if any were ever produced. From the picture it looks to be styled like the AM handheld that was mentioned earlier. The battery pack looks a bit longer and that doesn’t surprise me with the extra peak current needed for SSB. The folks at Wireless Marketing informed me that the power output is 4 Watts AM & 6 Watts SSB. The battery limitation was,-stated as the reason for the lower than legal SSB power output. If you remember the article titled Mobile Linear Amplifier Selection & Setup in our September issue the real life graph illustrated the change in dB as related to power output. The fact that this radio puts out 6 watts compared to 12 watts means you loose 3 dB, but that’s only 1/2 of an “S” unit, not much of a sacrifice for the convenience. The range will be much greater in SSB mode because sideband receivers are narrower, allowing less interference degrade the quality of the signal received, and are more sensitive than AM receivers.

Here are the features listed on their AH-100 marketing flier:

40 Channels AM/USB/LSB

LCD “Information Center” Incl. Freq. Display

Clarifier Controls

5 Preset Memory Locations

Auto Channel & Memory Scan

 Mic Gain, RF Gain & Squelch Control

Noise Blanker 

Battery Life Enhancement Circuitry

Dual Watch Channel Monitoring

Instant Channel 9

High/Low Power Selectable

Slide-On Rechargeable Battery System


The county of origin is Korea, the same as the AM handheld I inspected almost a year ago. Some of the features are the same such as scanning and dual watch that leads me to believe that they’re from the same factory. The CBS 1000 AM/SSB CB Base Station has a suggested list price of $499.95 and the AH-100 AM/SSB CB Handheld has a suggested list price of $349.95. Both units will be available in late November. Also they both have a 5 digit frequency display. A review of these two units is top priority! I’ll let you know any information as soon as I have it.Wireless Marketing has other products and accessories such as a small AM Mobile CB Model CM-5, seven different battery related accessories, cigarette lighter power kits, speaker mic, three different HT carrying cases and three optional HT antennas. ©CBWI

Questions about the Cherokee product line can be directed to:

Wireless Marketing Corporation
3701 Algonquin Road, Suite 750
Rolling Meadows, IL USA 60008
(847) 259-0641 (800) 259-0959
FAX (874) 259-0525

Update: http://www.cherokeeelectronics.com/index.html 

What’s Happened To Organized CB

With the inception of sideband there became a need to organize and educate CBers about SSB and it’s incompatibility to AM. Clubs cropped up all over the country for this purpose. There were AM & SSB clubs. When the license requirement was dropped, the general feeling was that the clubs would play a greater role in self policing the band. Over the past 10 years I’ve seem a decline in club interest and a rise in club ridicule. From deliberate interference during club on air activities including emergency calls to constant badgering of dedicated club members. What’s happening? Is this what makes some people happy? Could it be their way of showing their independence? I just don’t understand.

When the skip comes in from certain areas, I hear the same people fighting on sideband as if the feud just began and it’s every time. The same people must sit home on their radios all their waking hours to abuse one another. Some of our local operators insist it’s a recording, but if you listen and follow it you realize it’s live and stupid. Why don’t these people get a life? There is a lot to learn by being friends. It just seems inconceivable that anyone would devote all their time to making enemies.

What happened to the AM eyeball or coffee break? What about CB jamborees? These things were fun if they weren’t done too often. I remember going to CB eyeballs that had 75 to 100 CBers buzzing like bees at the local fast food restaurant. Also the SSB Sunday breakfasts had almost as many in attendance. Then the CB jamboree was the biggest event with hundreds to thousands attending. Most were weekend events and many campers planed their summers around the jamborees trying to attend as many as possible.

There were door prizes, raffle prizes, vendors displaying and selling their wares, manufacturers displaying their products, awards presented for individuals or groups that traveled the furthest to attend and so much more. Where did all this stuff go? Maybe in some areas of the county some of this is still going on. I know a couple of years ago there was a jamboree in Arizona. I don’t have any other information than that.

It would be invaluable to get your ideas on where you’d like CB to go. Do you belong to any clubs? What are they like? Are clubs good? Are get-togethers good? Would you attend a CB jamboree? What would you do to make CB better if you could? If you know of any club activities on 11-meters I’d like to know and publish them. Please check with the club official’s first. Also if you have any input to the questions or any related information, please FAX or mail it in. I think a monthly column on the subject will get some good ideas flowing. ©CBWI

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