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Midland 75-820 (822)

Mobile Com Adapter

Factory Specs

Modifications

Links

        This is essentially the same radio, made to the same design, and produced by the same company, as the old Cherokee AH-27 - almost.  The Midland has a few new features, and is a bit more well adapted to CB than the AH-27, which is a reworked ham radio. This is one of a new breed of high quality CB walkie talkies. They are a welcome addition. The newer 75-822 is the same radio, made a bit more difficult to modify, per FCC regulations.

        As a boy, I had a number of walkie talkies, as did many of my friends. These were the small 100 mw units, with extensible antennas, and a range of perhaps a block or two (the packaging claimed a range of a quarter mile). Despite their limitations, these were prized possessions, and inspired a number of baby boomers to become CB enthusiasts and ham radios operators in latter life.

        Better walkie talkies were available, but were expensive, heavy, and required a license.  As the baby boomers grew, the CB craze flowered, and millions of units were turned out, cost cutting measures and economies were taken, and some pretty poor quality radios started to be churned out. This was particularly true after the end of the craze, sometime in the eighties. It was almost as if the shoddy little radios of our childhood were returning.

        Even with the cost cutting efforts, it was sometimes possible to find a good quality walkie talkie. Though most of the distributers of CB radios did not take the limited walkie talkie market very seriously, Cobra and radio Shack had a few decent models out. With the end of the CB craze, the market became, as it was in the sixties and early seventies, smaller but somewhat more dedicated. Such a market was a bit more quality conscious than the previous mass market.

         With a return to a more discriminating market, came some higher quality radios. Among them were some new Cobra's, the marvelous Cherokees, and some high quality radios by Midland. This particular unit is produced in Thailand, though it takes many of the same accessories as the Korean produced Maycom radios sold by Radio Shack, Cherokee, and others. The basic layout is similar to these other radios, though it does differ internally, and does not use the same boards and components.

         The radio itself is built to a high level of quality, is reasonably well weatherized, and has a number of power options, as well as antenna options.  In addition to being able to operate on all forty CB channels, this radio can receive weather broadcasts, and is also amenable to mods permitting use of European frequencies and outbanding. There is a provision on the unit for an external speaker and microphone, as well as a standard BNC connector for attaching a better antenna. The top of the radio has these connectors, as well as the volume and squelch controls.

        The side of the unit has the PTT switch, as well as the buttons to step through the channels. These controls are all sealed and weatherproofed. This is also where the latch is located for the battery pack. In common with the Maycom/Cherokee series of radios, these controls are on the side of a blister extending off of the side of the radio body. This blister also has buttons to control the display light, as well as buttons for last channel recall and the function switch.

        Most of the other controls are on the front face of the unit, under the LCD display. These include the channel memory buttons, the high/low power switch, and the scanning button for scanning the entire band, or the five memory channels. There are also buttons to access the ten weather channels, lock the keyboard, and give immediate access to channels nine or nineteen. Everything is nicely laid out, well sealed, and of good quality. These radios will last a long time. Build quality is good inside and out, as I discovered when I disassembled the unit to tighten the antenna connector. I have included a photo to the right. Though no mods can be made from this side, it is nice to know that this is not a throwaway radio, and can actually be repaired.

        The front mounted LCD display indicates channel or frequency (Selection can be made between the two by holding the "F" key for about two seconds). It also has a multi segment S/RF display as well as indicators for battery life, TX/RX, mode, watch, power level, scan, and priority channel.

        Even with five watts on tap, the standard rubber duck antenna only gives a range between units of a mile or two. This might be extended to five miles or so when communicating with a mobile, and perhaps ten or twenty when talking to a base. The standard BNC connectors do accept a number of longer range more efficient antennas, though you then begin to run into problems with the unit becoming cumbersome. At the battery saving one watt setting, range would be a bit less.

        There are a number of power options, taking the form of several different types of packs which will slide on to the bottom of the unit. The standard included pack is the six cell pack, designed for 1.5v alkaline batteries. Also available are eight cell packs for rechargeable 1.2v batteries, as well as sealed nicad and NiMH packs. All packs are designed to provide nine volts. The battery packs are fairly universal, and this radio will take all of the Cherokee/Standard/Maycom packs. The newer generation of high voltage rechargeable batteries (usually marketed as precharged rechargeables) makes it possible to use the six cell pack with rechargeable batteries and suffer no loss in voltage or transmit power.

 

Mobile Com adapter

        The ultimate power source would be an AC power adapter, or a car adapter. Both are available. Slide on battery eliminators are available for these radios, as well as a unique adapter known as the mobile com. The Mobile com slides on in place of the normal battery pack, and permits the unit to be powered off of a standard cigarette lighter.

        In addition to the power adapter, the Mobile com has an antenna adapter which permits connection to a standard coax connector, for use of a base or mobile antenna system. Both connectors split off of a coiled cable which feeds out of the bottom of the adapter. This allows the unit to be used in the manner of one of those mobiles with all of the controls in the microphone head. The bottom of the radio, in addition to the power connectors, has a small numb that serves as an antenna connector, which mates with that in the Mobile com unit. Connected in such a fashion, the BNC connector is disabled. The two other screws shown in the photo to the right are used to join the two halves of the radio case.

        The Mobile com works with an entire series of related hand held radios from various manufacturers, and is a great accessory to have, for quick or transient connections. It presently comes standard with the nearly identical Midland 75-822, and adds a great amount of versatility to that radio. With the built in weather radio, and connection to an external antenna an power source, this might be a good choice for use in in a small boat.

        Use of the mobile com gives an honest five to ten mile range to this radio, perhaps a bit more, and extends its capabilities considerably. Used in mobile mode with this adapter, I get very good reports, and no one seems able to tell I am talking on a hand held. It is also possible, though a bit over elaborate, to plug in an external speaker and microphone.

        With the adapter, this makes a nice loaner radio, emergency radio, or quick install for a borrowed or rental car. it is also a popular choice for use with a motorcycle, particularly with the external speaker and microphone jacks permitting connection to helmet speaker and mike systems. It is then possible to disconnect from the adapter, and store the radio, or to slide on a battery pack and pop the rubber antenna on, and have a walkie talkie. The adapter also makes it easy to connect to an AC power supply an dbase antenna for home use.

        Though often bundled in, the Mobile com adapter is available for $20 - $30, as a radio accessory. As of this writing, the current midland high grade CB (model 75-822) is available with the Mobile com adapter included for right around $100. To my mind, it is worth the cost, just for the adapter, particularly if there is already a hand held or two around, that are compatible.

        As a part of a range of power accessories that fit compliant radios, I can use this adapter with my Cherokee radios, as well as the Midland. All three of the radios show in the photo below can use this adapter, the same power packs, and many of the same accessories, such as the headset and speaker/microphone. Its nice to have options.

        As I only have a pair of these adapters, and have something like six compatible radios, there is sometimes a bit of swapping going on. One nice feature is that I now always have a radio with me, due to the ease of installation. Now if someone would only made a compatible multi band HF radio.

Specifications

Specs on this radio are pretty good for a handheld, and as good as most mobiles these days.

Mods

        Like most modern production radios, there are a number of modifications that can be applied to this unit.  As this radio was designed to be marketed in the United States, as well as Europe, it is set up so that either the standard American CB frequencies can be used, or the 80 channel European band plan. It is also capable of using forty channel bands downshifted and upshifted from the regular United States forty channel CB band, which is the most popular mod to apply here in America. Applying this mod gives 120 channels.

 
  • Jumper only pad marked "A" for 120 channel operation. This will provide 40 normal CB channels, plus 40 channels above and 40 channels below the standard channels. Coverage from 26.515 MHz to 27.855 MHz. The "A" channels are not covered. (i.e. 3A, 7A, 11A etc.)
  • Jumper pad marked "A" and "B" for the new European 80 channel band plan. Channels 1 -> 3 are FM mode, Channels 4 -> 15 are AM mode, Channels 16 -> 80 are FM mode. Note that channels above channel 40 are lower in frequency then channel 1.
  • Jumper "B" only gives the UK FM mode band plan.
  • Next locate the feed through point labeled GND, this is the point that is grounded to provide a reset to the microprocessor
  • After changing any of these jumper pads it is necessary to ground the feed through at point GND to force a reset of the microprocessor.

 

 

 

Links
Radio Shack Manual for this radio eham reviews QST review.