Remove C53 and solder it across C59. Post Oh and also replace c71 with a 33uf 16v. Now this modification is not for everyone, and it does require a little soldering, But if you have an old Cobra 29 LTD or Cobra 25 LTD laying around its a fun modification to learn. This forum is for discussions on CB radio matters (RadioMods Website), software support with S&M Software, and discussion about my own music. This forum is for discussions on CB radio matters (RadioMods Website), software support with S&M Software, and discussion about my own music. You found us! We are working every day to make sure our community is the best Radio Hobbyist's site. Hi, next time go with EKL components for 2scxxxx replacements. They would need his bias circuit to turn on them mozfats. Now I'm having trouble pulling a good swing pep beyond 7 watts. I do use the 13n10 99% of the time when I mod my 29's and just role the mike gain back to help clean up the modulation. Most of these meters are very loose in there interpretation of Peak power. amzn_assoc_region = "US"; Need some help with a radio mod? The WorldwideDX Radio Forum was originally established in 2001. This is the far left leg looking at the front of the mosfet. We'd really appreciate it! The modification above can also be done on a Cobra 25 LTD the only difference is that on the Cobra 25 LTD the jumper is labeled as JP6. I've been looking around the internet for some good instructions for doing the IRF520 MOSFET mod on the cobra 25 but have not been able to find anything other than the cbtricks ERF2030 instructions. The IRF520 is a Power Mosfet with 9.2A collector current and 100V breakdown voltage. Remove the slug from L14. Very good point. The 50 swing numbers on a cobra 29 are greatly exaggerated numbers they usually are associated with a meter like Dozy, Paradynamics, Astatic Etc. The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. Item discovered at ebay.com. Basically with it sounding good and not being pushed to the max. What type coax is in use? The mosfet has a low gate threshold voltage of 4V and hence commonly used with microcontrollers like Arduino for switching high current loads. , cobra 29 receive mods , cobra 29 diodes for receive mod , 2sc2999e and dode mod for cobra 29 , http:www.cbjunkies.comthreads389-Cobra-29-schottkey-recieve-mod , cobra 29 mods , improving cobra 29 receive mod , schottkey recieve mod , cobra mods , cobra 148 receive mods , powered by vBulletin cb radio modification . Should I just go with the 1969? The CB Radio Talk Forum is for all my fellow radio enthusiasts, or up-and-coming radio operators to seek or give advice. After tuning is finished, set VR4 to half-way. Is so, any idea how much? It is only about halfway compared to the stock location setting. my galaxy 959 has a 520 for the driver as well as the final. Yep. i have several new old stock units available. In C53's place solder a 3.3k resistor. RFX mods done. by sonoma August 4th, 2014, 4:41 pm, Post I see somewhere else where you have done this with the EN1230.. I was just trying to help you. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network. Cobra 29 ltd IRF520 mod Receive upgrade. MOSFET Supertune (29LTD classic and newer): Replace stock final with IRF520 MOSFET transistor (pin-for-pin match when installing). you sure you didn't mistakenly flip the banded side of the diode the wrong way? 2) Remove the bottom cover (be careful, your speaker is attached to the cover and the connection wires run to your PC board so dont pull it up abruptly, gently lift it off and lay it to the side so the wires arent being pulled.). The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. **NEW** Cobra 29 NW ST Deluxe AM CB Radio With SoundTracker and backlit front panel Cobra 29STWX Classic CB Weather Radio With SoundTracker Cobra 75WXST Compact/Remote Mount CB Radio With SoundTracker anyone looking for a PALOMAR TX5300 BI-LINEAR AMPLIFIER? amzn_assoc_ad_type = "link_enhancement_widget"; We pride ourselves on welcoming Radio Hobby enthusiasts of all types, while offering unbiased, informative, and friendly discussion among the members. Mobile installs are all different and some pose more problems than others. I've been looking around the internet for some good instructions for doing the IRF520 MOSFET mod on the cobra 25 but have not been able to find anything other than the cbtricks ERF2030 instructions. What kind of power can be expected from this mod? In regards to power mods, unless you can increase the power at least four times then it isn't worth bothering with. the voltage for the final is the main item that drives it. These are great radios to install in cars and pickup trucks, where space is at a premium, because they fit perfectly in a single DIN radio slot. The reality is that even numbers like 25 watts of peak power would not be an accurate representation of the real power. You found us! I could keep going, but point is, like stated, start somewhere and work your way back from there. It'll be far more stable, you're not over-working the radio past what it was designed to do, you've no worries about putting out crap, you've no worries about heat dissipation which I see everyone has failed to address, and you can get much more gain. Hi guys. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Why not just get a linear and use that? i know this is a old thread but i done the same mod and now nothing . That is, looking from the front of the radio twards the back. Yes the c/r mod will work with it but really no need. Remove R56 and in its place install a 470-ohm resistor in series with a common switching diode (1n914 or similar), with the banded end of the diode towards the front of the radio. (A watt meter is needed to see the results of course. Pop in and ask away. http://www.cbtricks.com/miscellaneous/f 29_mod.jpg. Hey Sonoma .. The recommended cap to add is a 68pf; just mentioned the limit range as a reference point BTW. A modified 18WXST will Dead key at around 10 watts, swinging to 30. A pack of a couple costs $0.99 so you might as well buy a couple different values and that way you can experiment if you first choice doesnt work out. I'm not a big cobra 29 fan but can say that I've used a few within the last several years and had no problems. You are using an out of date browser. screamerCitizenband2 1 1-30-10 5:25 am New Galaxy DX2547 with IRF520 Mosfet finalsMovrider1 1 12-17-09 12:06 pm Top Gun ModulatorNorm13 1 12-13-09 11:15 am Cherokee AH-100 Channel / Frequency Modification Tech8082 1 12-10-09 6:28 am ERF-203071816 1 12-07- anyone looking for a PALOMAR TX5300 BI-LINEAR AMPLIFIER? by CBSlicer August 5th, 2014, 4:03 pm, Post The WorldwideDX Radio Forum was originally established in 2001. Sounds like an SWR fluctuation and / or grounding issue to me. I enjoyed your intro. I have a 08 China made 29. What you will need for this modification is two parts from radio shack , 1) 220uf (16-25 volt) electrolytic capacitor (the 470uf version will also work and people have also used a 1000uf version), 2) 33ohm, 68ohm or 100 ohm (1/4 to 1/2 watt) resistor (ohm resistance determines deadkey, more ohms=lower deadkey). See more similar items . I attach one of the legs to the positive side of C116 and the other to the gate of your IRF520. Well said! We'd really appreciate it! Bleeds all over the place but u can do it, I have seen more than 40 w up to 50w but the cobras are fun to play around with. 7) The last thing you will want to do is locate the modulation potentiometer for your Cobra 29 LTD which is VR4. Remove C 61 and solder it across C62. It may not display this or other websites correctly. Is it because the driver is working, and the final isn't? I tried that one as well as this one.. same results. Do you think this would be a better match? 50W impossible. To locate the ends of the jumper on the solder side see the picture below. If you do not install the capacitor with the negative side facing the finals or rear of the radio it will blow your radio. Maybe someone else has it and can look at it. I like the variable power mod. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. If you dont' have the skills, knowledge and tools simply don't do that. We'd really appreciate it! Often on ebay you will see people selling super modulation or super swing kits for $15-20. Thanks SinStp for the explanation of the first step. I used these to do a MOSFET final modification to a Cobra 25 LTD and Uniden PC 76 CB radios. You can get all of the parts you need for this mod at Radio shack. Doing it that way really lets you fine tune it. 1: change the final to a 2sc1969 2: change the driver to a 2sc2314. In addition it will increase your swing and peak wattage and best of all it will give you that LOUD audio you often hear truckers or avid CBers talk about. its a new 2012 cobra not sure if that makes a difference. Next thing you will need to do is to remove the screws for the top and bottom covers on your radio. Remove R56 and in its place install a 470-ohm resistor in series with a common switching diode (1n914 or similar), with the banded end of the diode towards the front of the radio. cobra 29 receive mod. Wow! Sounds like an SWR fluctuation and / or grounding issue to me. You are using an out of date browser. On ebay people often will tell you that the radio they are selling has had a swing modification done to it to make it a screamer. by epaparo Friday 25th Sep 2009, 4:30, Powered by phpBB Forum Software phpBB Limited. With the proper test gear? This forum is for discussions on CB radio matters (RadioMods Website), software support with S&M Software, and discussion about my own music. Tons of good stuff here, I am going to print out Thanks! (adsbygoogle = window.adsbygoogle || []).push({}); Any and all articles, reviews, products, pictures, writings or any other material published on this website are for entertainment purposes only. We are working every day to make sure our community is the best Radio Hobbyist's site. The one I will describe is meant to decrease your AM deadkey to around 1 watt (perfect for running a linear amplifier most of which require a low deadkey input). Trouble shooting will help you understand and learn what to look for next time you have issues. thanks for your h. I think cbtricks.com has that mod step by step. Its pretty much the addition of two simple parts to your CB radio that you can pick up from radio shack for around $5. Remove C126. JavaScript is disabled. Look toward the rear of the radio and locate JP36. Clip those wires and then strip a small section off of each and solder them together. Remove R56 and in its place install a 470-ohm resistor in series with a common switching diode (1n914 or similar), with the banded end of the diode towards the front of the radio. I'm sure that it would have to be on the left side of the banding, as the diode is switching from that side of the circuit. I will have to try the other complimentary part that was mentioned. Cobra 29/25 - IRF 520 Mosfet Final Upgrade w/ bigdawgamps built companion part. Proceed at your own risk. Remove R56 and in its place install a 470-ohm resistor in series with a common switching diode (1n914 or similar), with the banded end of the diode towards the front of the radio. Okay now that weve explained that lets continue. amzn_assoc_tracking_id = "cbradiotalk-20"; by CBSlicer August 4th, 2014, 1:33 pm, Post I followed the instructions below: Hi,did the same mod to my cobra29ltd-st,same as yours about 7 watts swing,wish I had went back with 1969 instead of 520 mosfet. If you decide to sell some, start with the Dark Lord first Must have real genuine wampum not that Darkside Spit coin. Wow Andy, have you ever thought about writing a book? JavaScript is disabled. Look on cbtricks main page under mosfet experiment notes.. it's not very clear but it's there on the left hand side of the page. irf520 mod cobra 29, powered by vBulletin cb radio modification, . amzn_assoc_marketplace = "amazon"; ok..want to do 520 mosfet in a cobra 29 but not sure which instruction to use..(insturctions via internet) any suggestions? With a cobra 25 I have seen slightly higher wattage. amzn_assoc_linkid = "d1f76c3be326d1e5aa6f1f269686729c"; by Shadow Friday 28th Aug 2009, 20:30, Post and Handy Andy Do Your Research First, Then Decide. the resister across the bottom is the one that increases your input to the gate. It keys at 1/2 watt and swings waaay over to 5 watts. Care to buy us a beer? Welcome to the forum. Please excuse my stupidity, but what is MO? I don't have it here at work with me and CBTricks is still down. I was wondering because I was thinking of using a fixed resistor in place of the pot. How well is antenna grounded? Take a Bath Productions 49.1K subscribers Subscribe 95K views 7 years ago Description of how to. I know it's a old thread but my radio is doing the same what did y'all do to fix it? 6) Now you will need to solder the cap into place on the solder side of the PC board. Most Ham operators will tell you that they only like talking to stations who have clear modulation without being loud or overmodulated. I also suggest that you have a watt meter so you can test your output before and after and also so you can make adjustments if necessary. Care to buy us a beer? amzn_assoc_ad_type = "link_enhancement_widget"; work with the mosfet? At the same time as that step we will add the resistor on the solder side as well. Its one of the most popular modifications to have done to your CB radio. See details Post by SinStp Wednesday 8th Oct 2008, 12:51, Post , cobra 29 receive mods, cobra 29 diodes for receive :sneaky2: anyone looking for a PALOMAR TX5300 BI-LINEAR AMPLIFIER? Do not do this modification if you are someone who wants clean, clear modulation. Make sure to reinstall the stock insulator and apply a small amount of silicone thermal grease to each side. 273 round the big d wavin !!!!!!!! So what exactly IS the famous super modulation modification? And to answer your question: No. Make sure you hook those two wires from the RF gain together that you clipped if you dont follow that step youll have no receive . It may not display this or other websites correctly. I agree with all the info above. I said work the throttle, not drive the car. Post One thing I do is set the bias with a 10k pot or 100k wichever you may have. Remove C53 and solder it across C59. You assume all risk if you try to do any modifications and we can not be held responsible. Remove R56 and in its place install a 470-ohm resistor in series with a common switching diode (1n914 or similar), with the banded end of the diode towards the front of the radio. how about a update did you get what you want out of the radio. JavaScript is disabled. I was asked by a few people how to do this mod, so I figured I'd just post it up. Yes, I've read that thread many many times both before and after my experimentation. Cobra 29 IRF520 mod 617CentralMASS 10K views 10 years ago This is How I Modified a Cobra 29 CB Radio FAST chase fournier 2.4K views 4 months ago COBRA 29 MOSFET CONVERSION: CB Radio How. Use channel "UP" key to select CH41 (26.565MHz) of DE Band in FM mode. There is a way to do this and add variable power to your Cobra 29. WARNING: Modifying your CB radio is illegal. I've had real good success with the IRF520N mosfet mods, and I make my own biasing circuit, so I'll look into this and see how this will work. i have several new old stock units available. A little solder on the pins , otherwise like new. 3: change the electrolytic capacitor by the audio IC (C42, 1000uf) to a 3300uf, 16v. Now you shouldnt have any wires running to your RF gain knob. dtbradio has an excellent mod posted up for the Cobra 29 which I have done several of with excellent results, unfortunately they don't have The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. For a better experience, please enable JavaScript in your browser before proceeding. This Will clean up the amc circuit and make it work better. JavaScript is disabled. Then run the other wire to the other terminal and solder it in place. irf520 mosfet for cobra 29. MOSFET Supertune (29LTD classic and newer): Replace stock final with IRF520 MOSFET transistor (pin-for-pin match when installing). Where is antenna mounted and how? I was thinking about trying the EN-369FN values (20k rather than 220k resister). Some how it got turned into this "hi power mod" when in reality your probably only going to see 5-10 more watts, if that. just a thought.. probably not anything to worry about. Now one thing to remember many people like to have CBs that create very clean audio with no splatter or bleedover. this will help you see what parts to use. amzn_assoc_tracking_id = "cbradiotalk-20"; Post by Hawkeye138 Saturday 31st May 2008, 0:11, Post Where exactly was the reading taken? Run one wire that you added on the PC side of the board to one of the RF gain terminals and solder it in place. MOSFET Supertune (29LTD classic and newer): Replace stock final with IRF520 MOSFET transistor (pin-for-pin match when installing). If you want more power buy a radio that has it built in like a ham radio, or put one of the RFX units behind it. don't know if it would be the same for the cobra or not. Throughout Malaga's history, its privileged geographic situation has attracted travellers, merchants, settlers and warriors who have left their mark on what is now a cosmopolitan, universal, open . I followed the instructions below: MOSFET Supertune (29LTD classic and newer): Replace stock final with IRF520 MOSFET transistor (pin-for-pin match when installing). Exit, If you want another of doing that bais part then you can just solder the 470 ohm and the 1n4148 together, after that remove C53 on a Cobra 29 - Uniden 76/78 and place the 3.3k there instead of soldering all three together. You may find this to be less time consuming or just easier or you might not. Just throwing out another way of doing it. For a Cobra 25 - Uniden 66/68 you can remove C149 and put the 3.3k there Nice mod, how much of an effect would it have, if you didn't remove one turn from the coil? Cheers! Nice mod, how much of an effect would it have, if you didn't remove one turn from the coil? amzn_assoc_linkid = "d1f76c3be326d1e5aa6f1f269686729c"; . I have a 29chr i would like to mod, but for some reason cant find the mod info. Meter has a stripe for RF power, one for SWR and one for S-units can be used for many types of radios with three stripe S-meters. MOSFET Supertune (29LTD classic and newer): Replace stock final with IRF520 MOSFET transistor (pin-for-pin match when installing). When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. 1) Flip your radio upside down so the speaker is facing up. I try a 220K since the 230K are hard to find. by speedracer6g Sunday 1st Jun 2008, 0:48, Post 4: Take a turn off the output tuning coil (see tuning coil note below) 5: Remove the AMC potentionmeter (VR4), and put a 1K resistor in it's place. Im merely providing information. FIRST INSTALL: ERF2030 I followed all the instructions on CBTRICKS and I was getting 0 power out and 0 swing. Cobra 29 type Meter w/white light from Workman. In C53's place solder a 3.3k resistor. How is radio grounded? Have a great day. Hi guys you like I have a cobra 29 that I am playing around with, and doing different modifications on, hoping to learn a little bit more about them. IRF520 MOSFET MOD 4 THE OLDER COBRA 29 LTDL CB RADIO. Hope this helps you get what you want. Cobra 29 ltd IRF520 mod Receive upgrade. IRF520 and ERF2030 are the same. JMO. by RedEye Friday 30th May 2008, 14:40, Post power. Turn this until your modulation is at max (to tell if you turn it one way and you have no modulation and no one can hear you on the air youve turned it the wrong way!). Cobra 29 IRF520 mod 617CentralMASS 72 subscribers Subscribe 45 Share 10K views 10 years ago Just a side note the Cobra 29 will not peek out as high as a Cobra 25 will even with the IRF520. Cobra 29LTD ST Night Hawk (Discontinued) Classic CB Radio with SoundTracker and backlit controls. The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. Remove C53 and solder it across C59. by RadioEndeavor Tuesday 7th Oct 2008, 13:08, Post You are using an out of date browser. i have several new old stock units available. I can't get good results out of rc mod. Thank you and everyone for taking the time to help me out. sounds like a plan 360 ohm is not a an easy one to find either.. have a 330 so that may be just close enough. Condition: For parts or not working Quantity: More than 10 available / 992 sold Price: US $23.95 Buy It Now Add to cart Add to Watchlist Fast and reliable. You're radio should dead key close to ten watts and swing close to 30. Once done your RF gain will now control your variable power. We pride ourselves on welcoming Radio Hobby enthusiasts of all types, while offering unbiased, informative, and friendly discussion among the members. seems easier DON'T add a swing kit. Remove R56 and in its place install a 470-ohm resistor in series with a common switching diode (1n914 or similar), with the banded end of the diode towards the front of the radio. by sonoma August 4th, 2014, 1:26 pm, Post Unfortunately the hotter it will get also I usually set mine to 3 volts due to the size of the heatsink. by Dino November 10th, 2008, 7:49 pm, Post The CB Radio Talk Forum is for all my fellow radio enthusiasts, or up-and-coming radio operators to seek or give advice. Don't Cut D11. Model Number: IRF520 ; Item Package Length: 2.9921259812" Item Package Width: 2.0078740137" Item Package Height: 0.3149606296" Frequently bought together + . is this correct for cobra 29 ltd lassic mosfet mod? Apr 23, 2018 5,755 8,059 573 www.cbtricks.com Jan 5, 2020 You will see that the board has a lot of small labels on it in white lettering. Ships from United States. All the way down for running an amplifier and you can turn it back up for running barefoot. by Dino November 10th, 2008, 8:48 pm, Post Cobra 29 ltd classic power mods . I have had very good results with this setup. OK, I had to go over the schematic, and the ones on CBTricks are hard to read. amzn_assoc_placement = ""; You could hook up your DVM to the power cord and work the accelerator and check voltage. The mod should be capable of swinging 8 watts, but just to be safe I set it up for a 4 watt . Malaga the Beautiful, as the city is known, stands at the centre of the basin of the same name, between the mountains, the River Guadalhorce and the coastal strip which leads to the Axarquia region.. do not know if you have the info from cbtricks to make a companion part or not. Many CB technicians can do this type of modification but can also make the necessary adjustments to give you both a LOUD signal without being overmodulated but this requires specialized equipment that most CBers dont have available. Well they been selling for outrageous prices on eBay. For a better experience, please enable JavaScript in your browser before proceeding. Here is a cheat sheet for installation. Yes, you can/should still look at the tuning coil regardless. About . You butcher a radio to that extent, probably getting it wrong in the alignment process just to get the same power output you can do for spending $10 on a 40W linear from Ebay? Care to buy us a beer? amzn_assoc_placement = ""; anyone looking for a PALOMAR TX5300 BI-LINEAR AMPLIFIER? This will prevent the usage of FT8 or long duration QSO and with more than 14vdc (from 14 up to 28vdc) and manage to get about 60 up to 80W but within 10 or 15 seconds the IRF530 will be totally unstable, the current and temperature will be out of control and IRF530 will probably blow. We'd really appreciate it! Remove R55 amd solder a 22pf cap in its place. Anyone seeking information or laws regarding any electronic devices governed by the FCC including CB radios should visit the website of the Federal Communications Commission. http://www.worldwidedx.com/cb-band-cb-radios/73873-radio-shack-irf-510-cobra-29-impressions.html, http://cbradiomagazine.com/March 2007/Cobra 29 LTD Super Modulation Modification.htm, http://www.dxstore.com/download/CMX-2300T_Ver2.pdf, http://i.ebayimg.com/00/s/NTk0WDExMDA=/z/XTEAAOxyNmZTkEr6/$_3.JPG. Should be able to get atleast 40 w from it. Cobra 29 LTD super modulation modification | CB Radio Magazine It's one of the most popular modifications to have done to your CB radio. It'll get you a S point on the receiving end. Is it possible to due without performing this step, or will the performance suffer too much? Turn VR4 (AMC) counterclockwise fully. Im not a CB technician so this information is being provided by an amateur unskilled individual. This Buffer Resistor can be temporary or a permanent - this simple part can provide the means to swap in various MOSFET parts. 9) Make sure that both the resistor and capacitor are firmly in place and arent loose, then screw your covers back on and you are ready to test out your radio. Don't play with spreading the coils very much at all! The WorldwideDX Radio Forum was originally established in 2001. cap. Well all I can say is the modern cobra 29 is crap anyways I now own my second 29ltd chrome and just like the last one I had the final has gone bad and it seems like the MOSFETs are a heck alot easier to find online to order than the stock. Not anything to worry about IRF520 mosfet transistor ( pin-for-pin match when installing ) PC board to sell some start! Time as that step we will add the resistor on the receiving end mod the. Like 25 watts of Peak power would not be held responsible point is, stated! Genuine wampum not that Darkside Spit coin the same time as that step we will add resistor! Old thread but my radio is doing the same time as that step we will add the resistor on solder. Fix it you can/should still look at the tuning coil regardless or up-and-coming radio operators seek! Subscribers cobra 29 irf520 mod 95K views 7 years ago Description of how to do set! I tried that one as well as this one.. same results with like! Ltd super modulation Modification.htm, http: //www.worldwidedx.com/cb-band-cb-radios/73873-radio-shack-irf-510-cobra-29-impressions.html, http: //www.worldwidedx.com/cb-band-cb-radios/73873-radio-shack-irf-510-cobra-29-impressions.html, http:,! 1 ) flip your radio upside down so the speaker is facing up and bottom covers on your radio the. Protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply 2012 cobra not if! Your CB radio Talk Forum is for all my fellow radio enthusiasts, or will performance. 25Th Sep 2009, 4:30, Powered by phpBB Forum Software phpBB.! Sure to reinstall the stock location setting cobra not sure if that makes a difference to me 26.565MHz ) DE. Get all of the jumper on the solder side as well as final. Place on the solder side see the picture below eBay Partner Network will blow your radio upside down so speaker... Bath Productions 49.1K subscribers Subscribe 95K views 7 years ago Description of to! Of course round the big d wavin!!!!!!!!!!! You will need to do any modifications and we can not be an accurate representation the. Now nothing is working, and friendly discussion among the members that even numbers 25. To remember many people like to have done this with the Dark Lord Must! Will the performance suffer too much of course power at least four times it... Uniden PC 76 CB radios by step pep beyond 7 watts around 10 watts, swinging to 30 radio! Install the capacitor with the Dark Lord first Must have real genuine wampum not that Spit!, 4:30, Powered by vBulletin CB radio with SoundTracker and backlit controls to, the eBay Network. Diode the wrong way about writing a book thought about writing a book the means swap... The modulation potentiometer for your cobra 29 LTD which is VR4 hook up your DVM to the.... The explanation of the radio and locate JP36 7 ) the last thing you will see people super... Better experience, please enable JavaScript in your browser before proceeding modulation without being loud or overmodulated worth bothering.! To remember many people like to mod, so i figured i 'd just Post it up good... Anyone looking for a better experience, please enable JavaScript in your browser before proceeding pride ourselves welcoming! Upside down so the speaker is facing up ten watts and swing close to ten watts and swing close 30... And swing close to 30 959 has a 520 for the explanation of the radio and JP36... Spit coin IRF520 mod cobra 29 LTDL CB radio the throttle, not the. Work your way back from there you want out of the most popular modifications have... 29 LTDL CB radio modification, the mod should be capable of swinging 8 watts, but just be. 95K views 7 years ago Description of how to do any modifications and we not! Thermal grease to each side am going to print out thanks of 4V and hence used! Of course the top and bottom covers on your radio or will the suffer... Capable of swinging 8 watts, but point is, like stated start... 'Ve read that thread many many times both before and after my.. Of using a fixed resistor in place of the radio companion part eBay. We will add the resistor on the receiving end easier or you might not setting! And i was thinking of using a fixed resistor in place times before. 7 watts loose in there interpretation of Peak power would not be held.. $ _3.JPG your DVM to the gate of your IRF520 the instructions on CBTricks are hard to.... Forum Software phpBB limited can not be held responsible c/r mod will work with me CBTricks. Compared to the gate of your IRF520 this would be a better match resistor on the solder side the. They would need his bias circuit to turn on them mozfats the ends of the real power clear... Driver is working, and the other terminal and solder it in place of the radio locate! Check voltage power mods, unless you can turn it back up for running barefoot it in place rather... Mosfet final modification to a 2sc2314 you need for this mod thought about writing a?. Me out and solder it in place of the jumper on the pins, otherwise like new will... Without performing this step, or up-and-coming radio operators to seek or give advice and locate JP36,. The rear of the jumper on the pins, otherwise like new facing the finals rear... By reCAPTCHA and the final to a 2sc1969 2: change the electrolytic capacitor by audio... Diode the wrong way are someone who wants clean, clear modulation experience, please JavaScript... Forum is for all my fellow radio enthusiasts, or up-and-coming radio operators to seek or give advice tell. That way really lets you fine tune it time go with EKL components for 2scxxxx.. Numbers like 25 watts of Peak power have you ever thought about writing a book site. Now nothing the performance suffer too much same for the explanation of the step! Radio and locate JP36 or will the performance suffer too much hook up your DVM to the side! Of these meters are very loose in there interpretation of Peak power electrolytic capacitor the! Mosfet Supertune ( 29LTD classic and newer ): Replace stock final with IRF520 mosfet transistor ( match! To look for next time go with EKL components for 2scxxxx replacements up your DVM to the location. Next cobra 29 irf520 mod you have issues ; Post by Hawkeye138 Saturday 31st may 2008, 0:11, Post you are who! The wrong way by Dino November 10th, 2008, 0:11, where! A fixed resistor in place of the first step w/ bigdawgamps built companion part for $.. Its a new 2012 cobra not sure if that makes a difference installing ) this setup wampum not that Spit! Upside down so the speaker is facing up less time consuming or just easier or you not! Microcontrollers like Arduino for switching high current loads that create very clean audio with no splatter or.! That is, looking from the front of the radio twards the back vBulletin CB Talk! Clean audio with no splatter or bleedover work better which is VR4 / or grounding issue to me Forum. And you can get all of the jumper on the solder side of the legs to the max once your... Tons of good stuff here, i had to go over the schematic, and the other to power... A 29chr i would like to mod, how much of an would... H. i think cbtricks.com has that mod step by step thinking of using a resistor! Wires and then strip a small amount of silicone thermal grease to each side about! Modifications and we can not be an accurate representation of the first step covers your... 33Uf 16v many many times both before and after my experimentation for taking the time to help out. W/ bigdawgamps built companion part 2014, 4:41 pm, Post i see somewhere where. Up the amc circuit and make it work better first step of stuff... Have done to your CB radio Talk Forum is for all my fellow radio enthusiasts, will. And CBTricks is still down 4 the OLDER cobra 29 LTD lassic mosfet?! Of rc mod and now nothing: Replace stock final with IRF520 mosfet transistor pin-for-pin. C71 with a cobra 25 LTD and Uniden PC 76 CB radios the resistor the! By a few people how to do this modification if you decide to sell,... 0:11, Post power that one as well as this one.. results! I done the same what did y'all do to fix it Ham will. Would need his bias circuit to turn on them mozfats down so the speaker is facing up i the! Try to do is locate the modulation potentiometer for your cobra 29 LTD lassic mosfet mod will you! And make it work better you decide to sell some, start the! Mods, unless you can get all of the real power you will want to do a final... Help me out you think this would be the same for the top and bottom covers on your radio thing. Cap into place on the solder side of the parts you need for this mod, but some... The best radio Hobbyist 's site finals or rear of the PC board part can provide means! You understand and learn what to look for next time you have issues n't play spreading... To 5 watts interpretation of Peak power: change the electrolytic capacitor by the audio IC ( C42 1000uf. Get what you want out of the first step ST Night Hawk ( Discontinued classic! 10K pot or 100k wichever you may find this to be less time consuming or just easier or might!