Back in the late 1980’s the biggest players in the scanner industry were RadioShack, Bearcat/Uniden and Regency. Every year one of these would make a splash and the others would follow up. Some of the notable scanners Bearcat had were the BC300, a huge desktop monstrosity with Service Search and a green display, and the BC210XLT, the last of the old “Wedge” designs. Regency introduced some AOR clones, the MX7000 and MX5000, which featured superb coverage, fantastic sensitivity and scan speeds best measured with a sundial. These guys had nothing on Radio Shack though!
Going Big!
RadioShack went big! Starting with the PRO2001 in the late 70’s as their first programmable scanner they kept adding channels, frequency ranges and other features before coming out with the PRO2004 in 1987. This was, for its time, the ultimate scanner! It had an unheard of 300 channels, full frequency coverage and was a tinkerer’s dream model. It is what made Bill Cheek a familiar name among radio hobbyists, he made a career of creating modifications for this and the follow up radios.
RadioShack soon bent to the wills of the cellular industry and blocked the cellular freqs from the 2004, only a few radios made it into the hands of consumers before a hastily (and manually) added diode was added to the 2004 to block the cellular ranges. While it was easily defeated, it was a harbinger of things to come.
All about the diode
Now, about that… D513 became famous as the one to remove from a PRO2004 to restore cellular coverage. On the very first batch it was manually added at RadioShack’s distribution center in Fort Worth. They had to open each box, remove the radio, then its case and solder a diode to the underside of the board. The second batch had that diode installed in the same matrix as others that controlled things like the frequency ranges, channel capacity etc. I had 2 PRO2004’s, one with the diode underneath (my first one) and a second with it in the matrix under a shield. The second one became sort of famous.
That metal shield was pressed on with compression tabs on early PRO2004’s. Easily removable, it was an inviting place to explore various capabilities of the radio. After I found out that the new cellular restoration mod was D513 under the cover of that shield I decided to see what the other diodes there did. There was a row of about a dozen, some of the spots were empty, others populated. By adding a diode where there was none or clipping an existing one various capabilities could be added or deleted. One restricted some low-band coverage, presumably for international markets, one added 100 channels to make it a 400 channel radio, one increased the clock speed, thus increasing the scan rate.
During my tinkering with the dozen or so diodes and empty tabs I ended up frying the board due to too much soldering heat. That cost me a $175 repair bill and when the radio returned from RadioShack’s repair depot that shield was spot-welded shut. It took an hour or more of work to get that open again so I could restore the cellular range.
There was an upside to this however, it was my first time named in a magazine article. I called Bob Grove at Monitoring Times with my results after his magazine had published a review of the PRO2004 and let him know what I found. He mentioned me in a follow-up in the next issue.
Did they WANT you to listen to cellular?
Now one has to wonder if RadioShack didn’t intend for users to listen to cellular phones (as they repeatedly claimed) why did the 870-890 range on the original batches come with the proper 30 KHz. spacing and that spacing was retained on the newer ones with the updated ranges and cellular blocks? Why did they make it so easy to modify the radio? Heck, as they went on, the 2005 and 2006 were even easier to modify!
Big and brawny
The PRO2004 was huge, with a big, bright LCD display, big membrane buttons and an all-metal case. It was still sort of a throwback to older desktop scanners with a non-removable AC power cord, but it had very modern features for its time just the same. It had no mounting options however for a vehicle. On one of mine I drilled a set of holes in the outer shell sides and found some short, low profile flat-head machine screws to insert into these holes, with the threads pointing out. The compression between the inner case and the shell kept them in place and I used a couple L-brackets to mount the radio under the dash of my car.
A few years later RadioShack introduced the PRO2005. This was a big improvement, if only for size and form factor. With all the same capabilities and features of the PRO2004, it was much smaller and easier to install in a vehicle. While it still had the non-removable AC cord and no mounting gear, the size and shape worked perfectly for my car at the time. I had a late 80’s Chevy Celebrity, one of the first front wheel drive cars of the era. This had a much smaller center hump as there was no driveshaft to the rear and left a lot more room for radios.
Getting a PRO2005
When a friend who worked at a Radio Shack store in Skokie, IL, just down the road from my home called me and said he just got a PRO2005 in stock I ran down there, and he allowed me to take it out to my car for a test-fit. The 2005 fit absolutely perfectly between the ashtray (cars had these then…) and glove box of the Celebrity and the grey color matched just about perfectly as well. I wrote a check on the spot. I am really dating myself here, writing checks, cars with ashtrays…
That afternoon I voided the warranty and found that D502 was the cellular switch, a simple clip of that and the full range was again restored, still with the proper 30 KHz. steps. I mounted it in the car by use of a couple L-brackets with very short sheet metal screws drilled directly into the side of the radio.
Eventually I had several of the PRO2004’s, the 2005 and later a pair of 2006’s. Since the cellular mode was so simple (a single diode behind the front panel) I did that to all of mine. On the 2005 I also did the Bill Cheek Expanded Memory Mod, which converted it into basically 16 400-channel memories selectable with a small DIP rotary switch. I had one set up for local freqs, another set up for Arizona, one for Wisconsin, another for Kentucky and some set for low-band and high-band so I could scan these ranges when skip was up. I also had CD-1 PL/DPL/DTMF decoders as scanners did not decode PL codes then.
Other radios of the time
RadioShack had a couple other radios that, while not as inclusive as the PRO2004/5/6 had great features and a lower price. The PRO2021 was kind of a “PRO2005 Lite”, similar in appearance but with only 200 channels and no 800 or MilAir coverage. The later PRO2022 added 800 MHz. coverage in a similar case. We all pined for a handheld version of the PRO2005/6 but the best we got was the PRO43 a few years later. It was a great little radio and included Mil Air and 800 MHz. The cellular bands could be restored but that was a little more complicated than on the big desktop radios.
RadioShack followed up on the PRO2004/5/6 series with the larger PRO2035 and then the PRO2042 in the 90’s. These had similar coverage but with 1000 channels and a tuning knob. AFAIK there were no cellular mods for these. I had one of each but quickly sold or traded them as they were too large for my needs and the 2005/6’s worked better for me.
Each of these radios would accept the OS456 or OS535 add-on boards, I talked about that in a different Scanner Tales article.
I had a friend in Wisconsin that had a half dozen of the PRO2004’s when they were still the newest radios on the planet. He had each hooked up to a band-specific antenna, one each for low-band, VHF-Air, VHF-High, UHF-Air, UHF Land Mobile, and 800 MHz. This system worked great and pretty soon he had OS456’s connected to them, and each connected to a PC running Probe.
Talking about Probe:
Now that I have mentioned Probe, let’s talk about that for a minute. Probe was a DOS-based software application that allowed one to operate certain radios and do thing like log activity and control scanning parameters. It also decoded PL codes, a great feature at the time. I had a couple OS456’s over the years then, installed variably in a 2004 and 2006 as well as a 2042. I also had a couple OptoScans in the same time period.
The OS456 was a computer interface that installed inside the PRO2004, 2005 or 2006. There also was a version for the PRO2035 and PRO2042. The OptoScan was pretty much the RF section of a PRO2006 merged with an OS456, kind of an early “black box” receiver, essentially a PRO2006 with no display or keyboard.
An OS456 equipped scanner could perform just as it would when not connected to a computer, but when connected to the PC with Probe, would become so much more. It really was a great combination. I even bought a tiny Fujitsu PC with a serial port adapter so I could run Probe in the field.
While these days this can all be done with a $40 SDR and free software, back then we were lucky to have these toys.
Time for Din Din:
Eventually Radio Shack went to DIN cases for their desktop/mobile scanners. These were GRE-made, and extremely similar to the GRE PSR series. The PRO197 was the premier digital scanner, eventually replaced by the PRO652 after Whistler took over the GRE designs. These two, as well as the GRE PSR600 and Whistler WS1065 were pretty much the same radio with cosmetic differences. One could share programming cables and files between them, as well as with the companion portable radios (PRO106, PRO651, PSR500, WS1040). While they were more practical for mobile use, these DIN radios just were not as cool on a desktop as the older models in my opinion.
Epilog:
The PRO2004, PRO2005 and PRO2006 were groundbreaking scanners of the time. While there was not much difference operationally between them, the latter two improved upon its predecessor while keeping with the spirit. I have less experience with the PRO2035 and PRO2042 but they too made improvements (except that the cellular mod was not possible IIRC). I was also not a fan of the case style, it was too big and awkward for vehicular mounting, something that the 2005 and 6 were better for.
Going Big!
RadioShack went big! Starting with the PRO2001 in the late 70’s as their first programmable scanner they kept adding channels, frequency ranges and other features before coming out with the PRO2004 in 1987. This was, for its time, the ultimate scanner! It had an unheard of 300 channels, full frequency coverage and was a tinkerer’s dream model. It is what made Bill Cheek a familiar name among radio hobbyists, he made a career of creating modifications for this and the follow up radios.
RadioShack soon bent to the wills of the cellular industry and blocked the cellular freqs from the 2004, only a few radios made it into the hands of consumers before a hastily (and manually) added diode was added to the 2004 to block the cellular ranges. While it was easily defeated, it was a harbinger of things to come.
All about the diode
Now, about that… D513 became famous as the one to remove from a PRO2004 to restore cellular coverage. On the very first batch it was manually added at RadioShack’s distribution center in Fort Worth. They had to open each box, remove the radio, then its case and solder a diode to the underside of the board. The second batch had that diode installed in the same matrix as others that controlled things like the frequency ranges, channel capacity etc. I had 2 PRO2004’s, one with the diode underneath (my first one) and a second with it in the matrix under a shield. The second one became sort of famous.
That metal shield was pressed on with compression tabs on early PRO2004’s. Easily removable, it was an inviting place to explore various capabilities of the radio. After I found out that the new cellular restoration mod was D513 under the cover of that shield I decided to see what the other diodes there did. There was a row of about a dozen, some of the spots were empty, others populated. By adding a diode where there was none or clipping an existing one various capabilities could be added or deleted. One restricted some low-band coverage, presumably for international markets, one added 100 channels to make it a 400 channel radio, one increased the clock speed, thus increasing the scan rate.
During my tinkering with the dozen or so diodes and empty tabs I ended up frying the board due to too much soldering heat. That cost me a $175 repair bill and when the radio returned from RadioShack’s repair depot that shield was spot-welded shut. It took an hour or more of work to get that open again so I could restore the cellular range.
There was an upside to this however, it was my first time named in a magazine article. I called Bob Grove at Monitoring Times with my results after his magazine had published a review of the PRO2004 and let him know what I found. He mentioned me in a follow-up in the next issue.
Did they WANT you to listen to cellular?
Now one has to wonder if RadioShack didn’t intend for users to listen to cellular phones (as they repeatedly claimed) why did the 870-890 range on the original batches come with the proper 30 KHz. spacing and that spacing was retained on the newer ones with the updated ranges and cellular blocks? Why did they make it so easy to modify the radio? Heck, as they went on, the 2005 and 2006 were even easier to modify!
Big and brawny
The PRO2004 was huge, with a big, bright LCD display, big membrane buttons and an all-metal case. It was still sort of a throwback to older desktop scanners with a non-removable AC power cord, but it had very modern features for its time just the same. It had no mounting options however for a vehicle. On one of mine I drilled a set of holes in the outer shell sides and found some short, low profile flat-head machine screws to insert into these holes, with the threads pointing out. The compression between the inner case and the shell kept them in place and I used a couple L-brackets to mount the radio under the dash of my car.
A few years later RadioShack introduced the PRO2005. This was a big improvement, if only for size and form factor. With all the same capabilities and features of the PRO2004, it was much smaller and easier to install in a vehicle. While it still had the non-removable AC cord and no mounting gear, the size and shape worked perfectly for my car at the time. I had a late 80’s Chevy Celebrity, one of the first front wheel drive cars of the era. This had a much smaller center hump as there was no driveshaft to the rear and left a lot more room for radios.
Getting a PRO2005
When a friend who worked at a Radio Shack store in Skokie, IL, just down the road from my home called me and said he just got a PRO2005 in stock I ran down there, and he allowed me to take it out to my car for a test-fit. The 2005 fit absolutely perfectly between the ashtray (cars had these then…) and glove box of the Celebrity and the grey color matched just about perfectly as well. I wrote a check on the spot. I am really dating myself here, writing checks, cars with ashtrays…
That afternoon I voided the warranty and found that D502 was the cellular switch, a simple clip of that and the full range was again restored, still with the proper 30 KHz. steps. I mounted it in the car by use of a couple L-brackets with very short sheet metal screws drilled directly into the side of the radio.
Eventually I had several of the PRO2004’s, the 2005 and later a pair of 2006’s. Since the cellular mode was so simple (a single diode behind the front panel) I did that to all of mine. On the 2005 I also did the Bill Cheek Expanded Memory Mod, which converted it into basically 16 400-channel memories selectable with a small DIP rotary switch. I had one set up for local freqs, another set up for Arizona, one for Wisconsin, another for Kentucky and some set for low-band and high-band so I could scan these ranges when skip was up. I also had CD-1 PL/DPL/DTMF decoders as scanners did not decode PL codes then.
Other radios of the time
RadioShack had a couple other radios that, while not as inclusive as the PRO2004/5/6 had great features and a lower price. The PRO2021 was kind of a “PRO2005 Lite”, similar in appearance but with only 200 channels and no 800 or MilAir coverage. The later PRO2022 added 800 MHz. coverage in a similar case. We all pined for a handheld version of the PRO2005/6 but the best we got was the PRO43 a few years later. It was a great little radio and included Mil Air and 800 MHz. The cellular bands could be restored but that was a little more complicated than on the big desktop radios.
RadioShack followed up on the PRO2004/5/6 series with the larger PRO2035 and then the PRO2042 in the 90’s. These had similar coverage but with 1000 channels and a tuning knob. AFAIK there were no cellular mods for these. I had one of each but quickly sold or traded them as they were too large for my needs and the 2005/6’s worked better for me.
Each of these radios would accept the OS456 or OS535 add-on boards, I talked about that in a different Scanner Tales article.
I had a friend in Wisconsin that had a half dozen of the PRO2004’s when they were still the newest radios on the planet. He had each hooked up to a band-specific antenna, one each for low-band, VHF-Air, VHF-High, UHF-Air, UHF Land Mobile, and 800 MHz. This system worked great and pretty soon he had OS456’s connected to them, and each connected to a PC running Probe.
Talking about Probe:
Now that I have mentioned Probe, let’s talk about that for a minute. Probe was a DOS-based software application that allowed one to operate certain radios and do thing like log activity and control scanning parameters. It also decoded PL codes, a great feature at the time. I had a couple OS456’s over the years then, installed variably in a 2004 and 2006 as well as a 2042. I also had a couple OptoScans in the same time period.
The OS456 was a computer interface that installed inside the PRO2004, 2005 or 2006. There also was a version for the PRO2035 and PRO2042. The OptoScan was pretty much the RF section of a PRO2006 merged with an OS456, kind of an early “black box” receiver, essentially a PRO2006 with no display or keyboard.
An OS456 equipped scanner could perform just as it would when not connected to a computer, but when connected to the PC with Probe, would become so much more. It really was a great combination. I even bought a tiny Fujitsu PC with a serial port adapter so I could run Probe in the field.
While these days this can all be done with a $40 SDR and free software, back then we were lucky to have these toys.
Time for Din Din:
Eventually Radio Shack went to DIN cases for their desktop/mobile scanners. These were GRE-made, and extremely similar to the GRE PSR series. The PRO197 was the premier digital scanner, eventually replaced by the PRO652 after Whistler took over the GRE designs. These two, as well as the GRE PSR600 and Whistler WS1065 were pretty much the same radio with cosmetic differences. One could share programming cables and files between them, as well as with the companion portable radios (PRO106, PRO651, PSR500, WS1040). While they were more practical for mobile use, these DIN radios just were not as cool on a desktop as the older models in my opinion.
Epilog:
The PRO2004, PRO2005 and PRO2006 were groundbreaking scanners of the time. While there was not much difference operationally between them, the latter two improved upon its predecessor while keeping with the spirit. I have less experience with the PRO2035 and PRO2042 but they too made improvements (except that the cellular mod was not possible IIRC). I was also not a fan of the case style, it was too big and awkward for vehicular mounting, something that the 2005 and 6 were better for.
