After the initial failure of the 13-853, I decided that I needed to send it off to a local CB shop for repair. In the meantime, I purchased 3 more 23-channel CBs for conversion - just in case :). One of them is a Midland 13-857 - the coolest CB radio I've ever owned.
Introduction
I purchased this 857 for about $20 from a Minnesota seller on eBay. When I got the radio it was a mess cosmetically, as expected though. After cleaning the faceplate with some IPA and a toothbrush, it looked so much better. I also cleaned up the knobs and whatever else I found to be dirty. Initially, it was very finnicky to get to work but a quick spray of WD-40 contact cleaner (no, not straight WD-40) brought this little guy back to life.
This would've been the CB I converted over to 10 meters...had my heart of hearts not said anything. I just couldn't bring myself to convert this radio after giving it a second look. It was so...perfect. It was the exact CB radio I'd always dreamed of owning, and one that I would've taken care of for years to come. So...I kept it stock.
And here is my review.
13-857 vs 13-857B
Now if you're on eBay and want to get one of these, I must tell you that there is a difference between the 857 and 857B. The one I have, the 857, is crystal controlled. It uses a matrix of 6 23MHz crystals mixed with 4 14MHz crystals. All of these crystals were good when I gave them a wiggle. In comparison, one of the CBs I received had the 23.290MHz crystal soldered on only one leg!
The 857B is a breed of its own but functions exactly like its normal counterpart. It is controlled by the PLL02A chip, a common chip found in many 70s and 80s CB radios. The interesting thing about this radio is that it too is 23 channels, not 40. 40 channels weren't introduced until January 1, 1977. Some CB manufacturers didn't stop making 23 channels until late 1977, so this would explain why some 23 channel rigs are date-marked 1977.
Overview
As I mentioned, the 857 is a crystal-controlled CB. This one has a feature called Delta-Tune, which allows you to usually tune 1.5KHz above or below your received frequency. The reason is that crystals overtime will shift in frequency, so giving you this easy flexibility would allow you to receive your buddy on the same channel if his radio had gone out of tune. It's only a 3-position switch, so a very crude RIT circuit. Odd and a bit useless for an AM set, but makes sense if it's crystal synthesized.
This radio also has a PA function and an external CB option. Basically, you could add a bullhorn to your car for a PA system or have an in-cab speaker system to that would help you listen to conversations on your highway route.
Getting to the PA system is very ingenious - instead of turning the channel knob, you can turn the squelch knob all the way down until is clicks off. Congratulations - you are now in PA mode!
Unlike the 853, the 857's S-meter works!!! It's very sharp, responsive, and keeps up with the chatter on Channel 6. Like those guys aren't S9+ anyways...
In fact the receiver is very sensitive. I just had it connected to a dummy load and Channel 6 was rolling in like everyone was next door! The TA7205P chip does an EXCELLENT job amplifying and pulling in signals.
What amazes me is that this radio is 50 years old. When I opened it up I barely had to clean the board, top and bottom. The PCB was near brand new!
Modifications
I GUESS I have to make some mods...
One being replacing the incandescent lights with LEDs. Since I'm a Bearcat, I figured that I'd replace at least the meter light with a green LED. Nothing big, just a small 3mm LED bulb. Or a multicolored bulb. The bulb will most definitely need a limiting resistor as it comes off of the 12V line directly. There appears to already be some form of limiting resistor in place, but I doubt that these are enough for LEDs.
Here's the photo after LED conversion. Not bad, and the white LED is not as blinding as the camera makes it. It's a very soft white, but my guess it's because it's near a chrome area of the radio. For now, the meter LED is a vintage green color like what my 93 Camry came stock with. Looks more yellow than green but hey, I think it looks cool:
Also, I found a really handy trick for making an LED light diffuse in all directions! Just use a file or sandpaper and gently abrase the LEDs tip until it is flat. This is helpful for your radios if your LED installations have what are called "hot spots" - blinding areas of light concentrated usually near the middle of the meter. Don't file down too far or you'll destroy the internals of the bulb easily! The light should go from a concentrated circled beam of light to a gentle hue of light in all directions.
This mod was easy to do by the way...
In the future I probably will peak and tune this radio. 50 years can degrade performance due to age and a fresh tune up would help this radio. However as of now I see no need to do so. L7 and L8 are the main power adjustment areas, with L9 being the TVI coil. When I hooked it up to the dummy load/power meter, I got a ~4.6 watt reading dead key - awesome!
Finally, this radio needs a new power cable. It didn't come with one and the one that comes from the other radio I ordered is crusty and falling apart. Amazon sells these for a decent price, so quite the easy fix. Don't forget the 2A fuse!
The radio isn't quite restored yet, and the chrome plating needs polished. This will be easy to do in a day or less.
Talkback would be an AWESOME feature to have! I've always wondered what I sound like on the air...
Ooh, and don't forget about a frequency counter! The PLJ-6LED counters are nice and will work great for this application. I think I'm going to stick with green LCDs and feed its input to the oscillator synthesizer.
Final Thoughts
If I were a young guy back in the 70s or 80s (well...I guess I live my life like I'm kinda stuck there anyways), this would be my most wanted CB radio by far. This is an absolute gem of a rig and in fact the 857B variant was part of the Midland Convoy Buddy series, which was promoted by CW McCall.
I think I'll definitely be holding on to this rig. And it's going to sit right next to my FT-891, I am THAT proud of it :) Add on a decent antenna and 4 watts of AM can get you anywhere when the conditions are right!
I'd like to try and reach my radio buddies over northeast of me in Parnell, Missouri. I'm thinking of constructing an inverted vee antenna with around 9 foot elements. I have more than plenty of space for such an antenna and an this antenna is not at all difficult to make. The center should be at least 9 feet or so off the ground which isn't a problem with my antenna hoist system. I suspect I'll be able to reach them as skip and DX have been beyond excellent around my area. DX usually shows up after 10 or 11am.
I've seen many hams convert these radios over to beacons by swapping out the 11.275MHz crystal for a 10.240MHz one. Like I said previously, it's a great idea - but for this model, I just couldn't bring myself to do it :)
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