• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

cobra 29 ltd classic power mod

Jul 1, 2006
20
0
11
I recently picked up a cobra 29 for 20 dollars from a co-worker. The radio worked good until I attempted a power mod I found. 1. Change R58(10 Ohm) to a 2.7 Ohm.
2. Change R123(1 ohm) to a .47 Ohm.
3. Re-tune L14,L13,L12 for maximum forward power.
I had no deadkey or swing after I repaced #1 and #2. I checked to see if any of the resistors repaced were touching existing parts but that was ok and also I rechecked the values of resistors just to be sure, ok. I have a swing mod(cap/resistor) done by a local tech, could it be this mod doesn't work with the swing kit mod or something totally different is happening here? I felt like it would not be a waste of much to attempt this, just thinking it was an easy mod. Thanks
 

I personally do not have a problem with swing mods , some do and some don't , Your mod you attempted really wouldn't have given you much more power if that's what you were looking for ? Your saying the radio worked fine before you attempted this mod ? Just put it back to the way you had it and make sure your soldering is good , and hopefully your 29 will be OK after that. IM guessing your swing mod had to do with running a amp ? That's OK as well , I honesty don't see any other reason for those then for driving an amp. If you wanted more power out of the radio , changing the driver and final would give you a little more. 1969 or Mosfet comes to mind. Good luck to you GLWAB
 
Thanks so much Switchkit. I think it was a bad joint cause I went back over both resistors and the radio started working right. Just like you stated, no power increase whatsoever.
 
Same to you guy! Switchkit just out of curiousity for future reference does the 2sc1969 really increase the power of a 29? Also, what other mods have to be done in order for it to work? Happy Holidays
 
Just a change to 1969 final will show you 5 watts more but in order to get the most out of it you have to change the driver final as well as do a few other thing to really make it work. I have a few 29's here and all i ever did was tune the radio to where i was seeing around 25 to 30 watts from a stock final and set the key at 4 to 5 watts and left it at that. My 5 pill Dave Made loves a radio set that way! The only thing a very low key (swing kit)will do for you is make your radio sound over modulated but its your radio so you do with it what you will. And in case you don't know..........have you ever heard a radio that was so loud that you could not understand what they were saying? That's what a radio with a mod kit sounds like unless you turn your mike gain back and then whats the point of installing a mod kit in the first place?
 
doesn't have to be anything fancy , 2314 driver and and a 1969 will give you more if 7 to 35 or more at 100% audio , I would say it was more power . You can do more to the radios if you know what your doing , Iv'e seen slightly over 40 watts pep at about a 8 watt DK , some radios are different then others. The Mosfets on CBTricks should yeld you about the same if done right. Yes , I like NPC mods as well as Cap resistor mod's ,and yes they do drive the amps better (maybe better is in the eye's of the beholders ?) as far as over modulation goes , you can do that on any radio that is quote on quote properly tuned. I find NC mics (RK-56 or 636s a good stock mic will get the job done as well) to work best with these mods , even blasting the radios , I have never ever heard some sound so over modualted that I couldn't understand them and if i did , chances are I wouldn't be talking to them in the first place. , folks like what they like weather others do or not. To each his own. My favorite last words come to mind .......I don't talk to machines , I talk to people. .........and in the end ,they are always the judges and juries on how I sound or how IM getting out.
 
I was thinking in the same lines as you, Switchkit. How else would you turn the deadkey down on a Cobra to let's say 1.5 to 2 watts and still get decent forward power.
 
you said it had a cap resistor mod , correct ? (that is also call a swing mod) What is it set at now ? Usually when this is done , the radio should be properley tuned first , really no need to cut anything in this case. Then the cap and resistor are used , the resistor determines what the dead key is there after . If you have had this done to the radio ? Where did the tech set your DK at on the radio ? If your not using a amplifier , I honestly don't see any need for a cap/resistor mod. Most 29s of today will do a good 5 watts to 20 at 100% modulation which is very nice , again ,no need for clip on those.......in other words , they have all the audio they would ever need on there own. Tell me more.
 
" set the key at 4 to 5 watts and left it at that. My 5 pill Dave Made loves a radio set that way! "

That seems like a high dead key for an amplifier with a driver stage. I would think 2-3 would be where you wanted to be.
 
The reason a set my key that high with any amp i own is because it has a better sound quality then the 1 to 3 watt range. Even Joe himself told me to set the key around 4 to 5 watts because anything less then that and they (Dave Made amps) sound like crap!

And switch.
If you have never heard a radio that sounded so overmodulated that you could not understand anything they said then you must not stay on ch 19 to often!
 
And switch.
If you have never heard a radio that sounded so overmodulated that you could not understand anything they said then you must not stay on ch 19 to often!

After 20 years I've heard a lot of bad sounding radios out there , and no , I do not frequant 19 very often . I've heard a lot of bad sounding radios on all channels over the years (everywhere) , over modulated / dirty amplifiers galore , but I could understand most of them and what they were trying to say over modulated or not , that's there business and they seem to be having a lot of fun in what they or doing , weather or not I think they sound like $hit or not. I suppose you can say I really don't care about "them" or "Whomever" but I do care about myself and others whom care about the way they sound or would like to sound. IM also a fan of good echo boards , but not to the point I can't understand what a guy is trying to say , most folks like that I wouldn't waste my time upon them (it was bad enough to hear them in the first place). Weather or not a radio has been modded or not , most have mic gains on them and can be set to be heard fairly nicely and understandable to my ear , it just does not have to be perfect with me , it just needs to be good enough . I don't make a living at this and have to worry about somebody else chewing me out a new a$$hole for what's fun about "my" hobby ? . Nor do I want to chew somebody else out for the way they run there hobbies as well. As I said before , you bet'cha !! the machines say one thing and people say another , I understand the theroy and why , but in the end , I talk to people and not machines. Some guys run Ameratrons and some run X-force `or Dave made , don't make no differance to me but like everything else , one is cleaner in the eye's of the machines then are in the ears of the people. IM not condeming ither one , IM just trying to have a little fun. It's not about condeming another for what they do , even though i hear so much of it ,day in and day out around places like these. It has never ever felt right to me , because for many ,it's about having fun , not so much by the numbers and why . I don't give a ratts a$$ about Bobby Joe's Truck Stop CB Shop !! you might or somebody else in this business might , but I don't. Oh sure ,it might be nice to know if they were spitting in the radios and charging me or somebody else a arm and a leg for there services , at least that way I could pass it on to someone else "if" they were to ask me. I don't believe in blacklists or whitelists , they all break the law , just some do better jobs at it then others. It's not my job to criticize, if I can help somebody else out , one way or the other , that's all that matters to me because others have taken the time to help me ,and still do. Are we having fun yet ;)
 
Yea Switchkit, it has a cap/resistor mod. It does around 1.5 watts and peaks at 19 or so. Really would like to try putting in a 1969 final but I dont think I have enough skills.
 
sure you do , you already tried one thing and weather or not it worked out for you , you still did it , it's the only way your going to learn. OK then , as far as your amp is concerned , I personally wouldn't change a thing , your just not going to get that much more swing out of it even if you were to change the driver and the final , at least not that much that will be noticed by the receiving end of your transmissions. As I said before , I think the 1969 and driver change are best for radios that are not running amps with them looking for a little more. Any questions ? feel free to PM me anytime. Peace

if you decide to change your final and driver , take your time , use a little heat sink compound on them as the others had on them , tighten down good but don't over do it , you have 3 solder pads on both units observe them closely and make sure they are the same way after the job is complete if you choose to do it. , with the cap/resistor mod in the radio , you could have a bigger DK after the job ? if this is the case the resistor will have to be changed for the lower DK
 

dxChat
Help Users
  • No one is chatting at the moment.
  • @ Wildcat27:
    Hello I have a old school 2950 receives great on all modes and transmits great on AM but no transmit on SSB. Does anyone have any idea?
  • @ ButtFuzz:
    Good evening from Sunny Salem! What’s shaking?
  • dxBot:
    63Sprint has left the room.