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Copy mark radio

hello everyone Larry you wd0 akx here and today I have a deck mark 10 a CB radio believe it or not in this package from about 1978 or so we're gonna take a look at I recently acquired this it does have a problem but we'll get that fixed here later but we'll take a look at the unit and it was made it's a 40-channel single sideband and I do have the complete documentation which is great as well as the schematic diagrams and all the alignment data and unit was made let's see here by MH Scott company and it's called a dak dak thank you pronounce it back or dak I guess and it's a markdown single-sideband 40-channel and look at those nice meters I just barely remember seeing this back in the 70s it's quite a radial it looks very impressive by all the controls and features and especially the large broadcast style meters like your broadcast studio so let's take a closer look at the radio the DAC mark 1040 Tanel single sideband AM PLL frequency then synthesized two-way radio CB communications transceiver I do have full owner's manual on it with alignment instructions and also which was nice get a PC board layout and schematic of the complete radio which is very nice to have without this that would have taken me much longer to troubleshoot my problem here so I was able to trace it out with the help of these manuals [Applause] [Music] [Applause] I'm telling you 4:27 [Applause] [Music] Oh on the front panel from right to left here on the bottom we have the volume control and the squelch control and the RF gain control this is a signal strength meter up here on top on the right for ECU channel selector switch the clarifier and the mode selector am upper sideband or lower sideband and your mic can mic gain control and then you have the SWR calibrate and the switch to calibrate check SWR and you can with the second meter here monitor your RF power output or your late current on the lower scale which is unusual for for a CB to monitor your plate current but it does have two finals and this is yes doubly our meter this is a modulation meter so it's quite interesting with the row of nice-looking meters there to monitor everything that's going on and a illinois' blank or switch on and off and this is your transmit you flip it in to transmit to otherwise saves on your tubes a little bit if you leave this in the standby mode if you're just gonna receive but if you're ready to transmit to power up the tubes here so that's controls on the front there's the internal speaker and behind that you see the main power transformer needs high voltage because the final output section astray do is tube type so we've got a tube final section here and there's a 12-volt DC power supply section for the rest of the radio here and what they use is a high gain board that's a common high gain board from a lot of high gain Seabees back in the late 70s turn the volume down a little but that is the final output section on the radio runs a legal power for watts am 12 watt sideband [Applause] [Applause] [Applause] [Music] here's a view of the bottom side foor yeah see the tube section tubes on top high-voltage area and then the main CB board high gain board and there's a lot of horror looking solder connections on that board looks like a lot of it backed at that time was probably all hand soldered or a lot of it was any home and this board was commonly known for cold solder joints which I did find one and that got the radio working took me a little while to trace out where it was there but doing a little troubleshooting and I ended up finding where I was losing voltage and was able to repair that and I brought the radio back to life seems to be working fairly good now here's a look at the rear side of the unit and there's a serial number of this radio as a larger speaker Jack and Terminal four a ground connection in the housing is made in Korea or possibly possibly the whole unit was made in Korea or assembled there here's a little closer look underneath the board there underneath the radio this is the high-voltage area for the final output yeah on the bottom of the high gaining CB board as you can maybe see some of those contacts don't look the greatest [Music] while of those contacts had to be refloat by hand it looks like one time after it was made maybe the solder flow machine wasn't working the greatest I am gonna go ahead and do the alignment that's in the manual on the VCO circuit and the sideb and the clarifier doesn't seem to be quite centering right now so there's alignment points here and right back here for the sideband alignment get the upper and lower sideband I'm clarifier to work right and this is the VCO area here and I did check that and that's within spec within range said okay here's the PLL frequency chip down there it's on upper 38 or lower 38 excuse me sideband and 38 and we'll check out the Super Bowl Channel channel six and conditions are very hot today as you can see in the signal strength meter s9 signal air constant constantly here on channel 6 there's so many talk and it once it's just all girly [Music] [Music] the only thing I don't like about the squelch is it has a popping sound every time the squelch goes from closed to open and that's kind of annoying [Applause] [Music] no fee I don't know if you can hear it in the mic here or not but when it's quiet and then when you get a signal it's kind of a popping noise [Applause] well I did do some basic alignment on it according to what the manual had to say good thing it came with the manual and the diagrams here so I'm satisfied now with the settings I think I'll go ahead and put it back in the cabinet with all those screws all right well we got everything back in the housing here and get it all boxed up and I did find that problem with the cold solder joint the transmit and receive was dead when I first got it but I did trace that out and once I got that solder joint taken care of everything came to life on it but the alignment was off somewhat especially on sideband so I went through the alignment procedure in the manual as close as I could got everything pretty much back to spec as far as performance I don't like that high game board in there with all the poor soldering in that and that board was never a really terrific CB as far as I'm concerned so a ringing of 0 to 10 for performance and great this radio at about 5 the power is barely up to spec on it and as far as look so you gotta say it's a 10 you're not gonna find a CB that looks any better than this I don't think all the fancy meters and nice styling but I guess it's not gonna be my main radio it's gonna be more or less for looks and occasional use I'll stick to my Cobra 148 GTL I guess for performance so there you have it DAC mark 10