Cobra 2000GTL what a channel switch "mod" is and how it works.

[@homefront3162]

I JUST bought a 1981 2000GTL with 2 speakers, the wood and front is amazing good. The only mod was 4 wires jumped to the PLL and the NB and PA switch, the inside is old but workable, I am going to do a full resto myself.... lol wish me luck.

[@oldrango883]

Just got one of these yesterday and this just taught me how to make my channel map. Thanks!

[@homefront3162]

My 1980’s 2000 only had the cb/pa switch and I received all the extra channels. It had a wide clarifier as well. I had no idea how it was done

[@tru2Seattle]

I just subscribed, these videos are awesome for Radiohead’s.

[@VintageElectronicsGeek]

I remember when these things hit the scene, everybody wanted one, they were hotter then fire back then!

[@1112223333111]

my buddy has one with the "expo" kit and you cant center the clarifier on U, L and am when you go up or down a band. It might be 27555 on lsb but it will be 27558 on usb, etc. normal 40 is centered though on u,l and am

[@TheRadioShop]

Don't forget about the secret CB book mod. 2 pole 6 position switch. Was one of the first I saw back then.

[@mikesradiorepair]

I did a (hmmm, what was that radio) Midland 78-574 (02A chassis) that had a 2 pole 6 position channel mod. God trying to map that outs a pain. Customer bought it and couldn't figure out what the knob was for. He said "I turn it and I don't hear anybody talking anymore". I told him that's a good thing, he shouldn't be on those frequencies anyhow so he had me remove it.

[@dennisthomas4766]

I have a radio just like that that has upper and lower channels and has 6 "toys" on it, I bought mine in 1998 for 200 dollars and a Antron 99 antenna and a D204 Power Mike

[@theradiomechanic9625]

28.045/28.085 right into the low end of 10 meters...fortunately it is the CW portion so they won't bother most folks.

[@mikesradiorepair]

Most of these people only go to about 27.555 or so for the international skip.

[@gooberminther3tik25]

Just received Cobra 2000 GTL with Switch Mod. Have no idea when it was done. And dont like it. My question: What is your opinion of DDS-VFO mod? I dont use NB though ANL is useful. On my Strykers, 655 and 955, I use HIC (high cut) always; takes the edge off.

[@army19661969]

Mine was hooked to the speaker switch ( 1st one ) up= high channels, middle= 1-40, down= below channel one

[@SuperJV4x]

do you know if the faceplate is anodized? I got one with cigarette tar and the previous owner started to clean the faceplate - yet it is so shiny silver where they cleaned that I fear they removed the anodizing. Not sure to leave it or take it the rest of the distance - though don't know if its possible to do that and leave the lettering. Any advice appreciated. Thanks

[@mikesradiorepair]

SuperJV4x Tthe faceplate bezel is chrome plated plastic. The faceplate trim plates that have the silkscreen printing are aluminum.

[@charleszimmermann7784]

I love the information in your videos, I see most of these vids are older are you still repairing radios, I have a Cobra2000gtl and it has been modified and is off frequency I would like to get it gone through, put back to stock and adjusted. If this is something you still do?

[@douglasbollinger3626]

Mike - question for you - I prefer stock / un-messed with radios, but I just bought a Cobra 2000 GTL used. After testing all the functions/switches I found out it was modified for extra channels only on the speaker selector switch. Speaker 1 & 2 together position is regular CB freq's. Speaker 1 and Speaker 2 (separately) positions are the extra channels. Only speaker jack # 1 works for the speaker. (PA jack still works.) Speaker # 2 jack doesn't do anything. (The NB and ANL switches haven't been messed with as far as I can tell.) You mention "cut" circuits in this video. Is it possible to remove this mod and get the speaker switch working for the speaker jacks only again and back to just regular cb? Also, I see a D35 (I think it was 35 when I had it open looking at it) was coming out of the board on one end only, then a wire soldered to the end of D35 going somewhere -- instead of the diode being soldered to the board from both ends like it should be. Is that part of the channel mod possibly? I'd like to get this radio back to regular 40 channel CB only and switches working like they were meant to. Everything else works fine on the radio except the speaker selector switch due to the mod someone did. Any help is appreciated!

[@buckaroobonsi555]

I can not believe that they did not notice the freq. counter changing? If they go to a mod site they can get a channel map and it will tell them what channel to use each switch. It will give them a map based on which PLL they have in that radio if they used multiple PLL's? They have better modifications to day that will give him aprox 26Mhz-28Mhz with all the skipped channels and A channels and the 10KC etc....in a continuous tuning fashion with no need for band switches or PLL switch positions and the like. No adder's and no having to rebuild the channel selector etc. That is a nice looking Cobra 2000 who ever owned it took care of it cosmetically!

[@mikesradiorepair]

I get the feeling the person that bought this radio had never had one before. It is probably their first radio with a switch modification. Yep, much better ways to do it these days. Small microcontroller module and you get continuous tuning. Personally I'll never understand why people need extra channels. It's not like all 40 channels are busy like back in the CB boom days.

[@buckaroobonsi555]

Wow that is a nice first radio!! My first was a Radioshack 40Ch that was slightly bigger than my hand. No adjustment pots at all. When you clipped the modulation limiter the radio would not over modulate and it would do 4 watts swinging to 12. So that is a nice first radio.

[@williamcolvin3609]

Because you have some people like he described that have a 40 channel radio and have nothing better to do than find where someone is talking and use their noise toys or just key up to irritate. That is why one up and one down will usually work just fine.

[@williamcolvin3609]

Upper and lower 40 might get you out of the Mexico S-9 Noise where you can talk to someone without those people you have no clue what they are saying drowning you out.

[@maplelagoo9001]

Do you still take radios? I have a Cobra 2000gtl that needs to be aligned I think.

[@bobicpfan2]

no. he hasnt taken in any in a very long time

[@DAVIDGREGORYKERR]

why can they use a proper PLL modification so as to have all the channels a person could want.

[@williamcolvin3609]

Mark19960 makes a board that does all the channels and Mike installs them as they are dealer only item I think he calls it the King Channel Mod. Mike can explain more and I believe he has a video of them being installed and how they work.

[@bobicpfan2]

put pin 10 of the PLL chip to ground and it goes up 64 channels. 27.405 plus 64 is 28.045. put pin 11 of the PLL chip to ground and you go down 32 channels. 27.135 minus 32 is 26.815. put both 10 and 11 to ground and it goes up 32 channels. 27.135 plus 32 is 27.455

[@Tobinindustrial]

I have a pre installed mod on my Cobra 2000 but it is only two switches and no matter where I put the switches the radio always reads one frequency low. Example. Channel 2 is 26.965 and Channel 1 is 26.955. I've had this radio for some time now and no luck with it

[@LeapFrog_Radio]

Was a part swapped out from a previous mod or was it just the alignment issue? Thank you

[@emerituse3390]

Crystal kits kinda sucked. You could only have all of your modes (AM/USB/LSB) aligned with one crystal only. Once you switch to a different one, everything would be off. With the switch mod, there was one other thing you did have to change in the 2000 for extra frequency coverage. The PLL. Change from the 8734 to the 8719. Personally, I preferred the mod with the 11.125 crystal and 2 DPDT center off switches. 26.125 to 28.045 with no skips. :)

[@mikesradiorepair]

The better solution will be when Mark gets his frequency counter and DDS channel modifucation board up and running. That will be the ultimate mod. Not only a channel mod but a update for the ancient counter module and easily programmed roger beeps, noise toys and other snazzy stuff.

[@williamcolvin3609]

How will the frequency counter be installed on radios that did not have a counter?

[@rh7root]

Hi Mike. Do you have one of those for Sale

[@Scott-K7sce]

i have a 2000 with a 2 switch mod 8719 chip. undone clarifier it since when haywire sits in storage untill a later date i have a 2nd 2000 that works good no extras however i used to because of the switch board it stiched together the RX is low, the limiter is missing, the d52 diode is cut out ya know i really wish the but nuggets, screwdrivers would leave well enough alone now it's up to me to get both radios put back to factory out of the box condition

[@mikesradiorepair]

Welcome to the wonderful world of demodification. :)

[@Scott-K7sce]

lol ya. well at least all my ham radio(s) arent messed with and but nuggets wont get anywhere near them... 73's

[@williamcolvin3609]

Whole lot easier to go by instructions to mod a radio - than it is to find and repair all those mods that have been done.

[@soylentgreen6476]

I love my stock (unmodded) 2000 GTL.

[@mikesradiorepair]

Yep, I'm with you there. Unmodified with nothing more than a fresh set of electrolytic capacitors and a transceiver is all I want out of a CB.

[@kenneth6731]

Screwdriver expert mod!

[@francismcclaughry3794]

I had one of these radio's it would go up I had no desire to go down. mine went 28500 in the ham band, but it was flaky up on the ten meter band I had two speakers with time. I'm so sorry I got rid of mine. I miss it. but now if you wanted one it would cost a fortune to own one.

[@williamcolvin3609]

My Washington a just purchased off E-bay has the three switch mod and without a counter that does not impress me - I would much rather have the crystal mod. The Crystal mod would be accurate and would not need a counter - and most people do not use a headphone jack,so it stays pretty much factory. Thing is those old basic one up and one down board are not that easy to find. Most of the older guys that grew up with these radios could care less about twelve bands one up and one down that is it.

[@buckaroobonsi555]

I think it is mostly for international DX. 27.555 is a hot spot. I have never felt the need to have to go off into illegal territory to talk to someone! Some people I think want the illusion of privacy which to me is silly just go use a telephone of send an email. Some people want a channel that most people do not have for hunting etc....For me the appeal of a radio like the 2950 is rock solid SSB a little more power than 4 watts and if I decide to get my license this Winter I can use it on 10m and 12m and it has dual VFO's for repeater use and can be used with CTSS tones etc. My Lincoln was inherited from a relative. I do not talk where I am not allowed even if the capacity to do so is there. My relative that had it had it for the SSB stability and the fact that it put out more than 4 watts cleanly. Truthfully 4 watts just does not get it done with DX from Mexico and South America rolling in at S9 all day long and all night long. I also get Russian DX freq.!! On top of the old people I want to talk to are not in my back yard. So I need more than 4 watts but I do not need 600w or 1200w or 3000w. I also like being able to turn the power down to 1-2 watts when that will do just fine. The people that live in my town and talk on CB are mostly trash that are vulgar, bigots and such. They tend to stay on AM so I tend to stay on SSB and it is a match made in heaven! LOL

[@mikesradiorepair]

Lucky for me the two local groups that are on AM in the evenings around here are good people and not a bunch of loudmouth nut bags.

[@buckaroobonsi555]

Very true. The main reason I am thinking about getting my license is to open up the door to legally communicating more than 150 miles away and the legal power output allowed. I have to say most of the Amateurs I have meet have been just as bad as the those they dislike and speak down too. A bigot is a bigot no matter how well educated they are or how deep their pockets are. We all have area's where we are smart and have specialized skills or knowledge but that buy itself does not make one better than another or give one class or character! I understand some of them must be good people but the same could be said about CB radio! LOL So I like SSB because I like to talk and I like to talk for extended periods of time with people about really stupid stuff! I like to talk to be not in my backyard! LOL I have no time for agitators, noise toys, splatter boxes etc....LOL Nothing is a greater gift than having decent good people around you.

[@dinkhu215]

Mine uses the tone knob

[@buckaroobonsi555]

I do not know. I like modded radio's if the modification is done right. The problem with modifications that most people try to save a buck and do it themselves and butcher it. Even worse they pay good money but take it to a person that is going to butcher it. What I hate on CB is noise toys, agitators, ghost talkers, broadcaster's, splatter box radio's over driving poorly designed and built splatter box class C non-linear linear amplifiers with no filtering. Oh and bare foot over modulated splatter box radio's and 4 transistor high power export radio's with all kinds of 3rd order harmonics right from the factory! Guys that think they some how own the exclusive use of a channel and last but not least CB'er dumb enough to think their are rules on which mode of SSB you use on various channels as in USB or LSB! Last time I checked with the FCC Ch 1-40 could all be used on AM/USB/LSB at your whim! Almost forgot the use of all kinds of vulgarity on CB ticks me off too! I forgot about the SuperBowel on channel 6! If ever the FCC needed to crack down on people it is everyone on Channel 6 doing HiFi AM and running insane wattage in the 3000-20,000 watt range. People behaving themselves like gentlemen on illegal channels on clean radio's with clean power that only use what they need I am fine with them. The people who's bandwidth they are using might not be. Always best not to anger local hams if you like your money, equipment and your freedom! Don't get into the neighbors tv or garage door or peoples phones and computer's and life will be good. In fact if you look at it one way an export radio is a FCC type D accepted CB radio that has been modified by the manufacture. In the old days that meant binary adder's and encoder's and extra crystals or dual finals or larger more powerful single final etc....If you look at it from another perspective a FCC accepted Type Radio is a much better radio that has been stripped down to meet the FCC's requirements by removing original circuitry. So if a board is missing parts on the board from the OEM that means it has been modified to it's current form to make it type D accepted. A lot of ham's modify their radio's and amplifier's for MARS even if they do not have a those privileges. Ten-Tec/Icom, Kenwood, Yaesu, Ameritron,Alpha, Dentron, Collins all had modifications. What do you think the Aux position was for on HF Ten-Tec's that already had all the HF or HF+6m bands clearly marked with only 11m being skipped on the selector. Their is nothing I hate more than a radio that does not have continuous tuning that skips over chunks due to band allocations. IT would be just as stupid as limiting all car's in the USA to 70Mph electronically what would be the point of owning a sports car, a luxury car or exotic car? Generally we should trust people then punish the guilty not protect people from themselves with electronic babysitters. Also we all know a ham that is using his Amateur gear to talk on CB which is very much illegal but no one says anything. You can always tell it is not like anyone with ear's can not tell the difference! Sometimes breaking the rules is no big deal and does not bother anyone.

[@michaelporter351]

were is the lowers

[@mikesradiorepair]

It doesn't have any without doing a modification using a crystal.

[@Chuck-U-Farlie]

you should be able to get down to 26.815 without changing to the 11.1125 crystal. i think i saw you get 26.915 in the video.

[@felipevillarreal5624]

Cuanto cuesta El Cobra 2000 GTL

[@garyhopkinssr8561]

If I could afford it I would send my Cobra 2000 GTO to you I would maybe someday

[@bobicpfan2]

he no longer takes in any radios

[@NoName-bt3oy]

I would have thought the PLL has a fixed span, no matter how it is encoded (some form of BCD no doubt). A case of getting either the correct encoder, or at most an arduino(could do freq readout too then).

[@mikesradiorepair]

They didn't have arduino back in the day when someone did the channel modification. There are a limited number of possibilities on how you program the input pins on the pll. The switch modifications allow you to change that programming and therby get "extra channels"

[@NoName-bt3oy]

I meant as of now. You could take that radio(any CB) and make it all it can be, for what it's pll and RF stages are worth. Should be able to do a kit with different software to suit many models.

[@mikesradiorepair]

+NoName And doing that cost money. This radio was already converted and the customer didn't want anything like that done.

[@NoName-bt3oy]

Only a suggestion.

[@mikesradiorepair]

+NoName There are ready made kits available to do it. Hard work has already been done. :)

[@1OFGODSOWN]

Very overrated CB and extra channels are totally useless as well. I want my radios peaked and tuned and that is it.Channel 1-40 is enough since you can’t talk on but one at time.

[@animalcorvair]

i stay on my channel 15 most of the time ..i hate mods like this get a ham ticket if you want more channels ,,,thats just me

[@mrkattm]

illegal, I guess it is anything for a buck.

[@mrkattm]

Luckily they are only in the lower 10 meter ham band which is CW and those guys can plow right through the free banders if they choose, What is really disturbing to me is that a lot of these guys, here in the Tampa Florida area, are hanging around the 28.500 range, which if memory serves me, is reserve for the forestry dept. Which might not be a big deal in Florida but it could proved problematic in the Northern to North West States esp. during fire season. But hey anything for a buck right!

[@mikesradiorepair]

+Michael Katt I sure in the heck didn't perform the channel mod. It was like that from a previous owner. Personally I like old tube cb radios like the Johnson Messenger I. On CB's four channels on AM is all I need, 12, 17, 19, 32.