Cobra 138xlr alignment. Has the MB8719 PLL in this radio.
Cobra 138xlr alignment. I have heard that the 135 XLR was the same radio, but CB tricks still does not have anything listed for alignment of that radio. dxradioshopny. Cobra 135 has relay controlled mode switch for better isolation, massive Nov 18, 2021 · Thanks. Oct 20, 2014 · http://www. Includes alignment Had to crack open this newly finished Cobra 138xlr to do some troubleshooting and repair. Cobra 138XLR / 139XLR Service manuals and technical schematics for COBRA 138XLR SAMS Photofact® manual, Cobra 138XLR Documentation Project CBTricks. I don't have a Sams of a 138XLR or a picture of a stock one, but I have no reason to believe it wouldn't follow the schematic. Compared to my 449 this radio is really well built, it puts out a full 20W no sweat and even has a power choke on the speaker plate. It has 40 pages and is dated 7/1977. I will do a search for probes and hopefully get that ordered tonight. This is the same board as the 138XLR, original President Washington Apr 11, 2009 · Does anyone have the complete alignment information for the old Cobra 138 or 139 radios? This is the 23 channel radios. Cobra 138XLR two-way radio pdf manual download. 9 of 10 Cobra 138XLR and the Cobra 139XLR with a bad reception or no RX the problem is the TR5. **NEW** Cobra 148 NW ST Top-of-the-line CB Radio With SoundTracker and backlit front panel Cobra 148F (Discontinued) Cobra’s top-of-the-line SSB Mobile with Frequency Counter. The new radio was called the Sidewinder. It includes modifications such as cutting resistors or capacitors, removing components, and replacing voltage regulators or other components. ?? Yankee Member Username: Yankee Post Number: 78 Registered: 7-2003 Posted on Thursday, April 01, 2004 - 12:54 am: What would the Cobra 138 xlr and the cobra 132 xlr put out if aligned properly. Secret CB Volume Twenty-Eight Aug 21, 2006 · Attachments cobra_138xlr_139xlr_tb1210a. It is probably the most well-known line Oct 24, 2021 · I am buried in repairs atm. com/DXRADIOSHOP Brands: Cobra Galaxy Ranger (RCI) Super Star Uniden Midland Miscellaneous tips Cobra Cobra 148 GTL and F-GTL Extra Channels: Locate the MB8719 chip (usually right behind the channel selector). This lets you select around 90 channels in 3/4 of a dial turn on a 40 channel dial but still acce Re: Cobra 138XLR Low power output. Nov 18, 2021 · Hey everyone out there. Meaning the output is bigger than the input. I am hoping I can find the alignment for the shakespeare gbs 5000 by looking at a similar model or to see how close I can get an idea and get it back home soon. Detailed Instructions Cobra 138 XLR AM SSB CB Radio (1977-78) cbradiomagazine 39. Photofact CB Radio Series service manual pages for the 1977 Cobra model 138XLR. ?? Yankee Member Username: Yankee Post Number: 78 Registered: 7-2003 Posted on Thursday, April 01, 2004 - 12:54 am: Secret CB Volume Twenty-Eight Documentation Project CBTricks. The year was 1963. Thanks again. 2. A few restoration tips. Photofact CB Radio Series service manual pages for the 1977 Cobra model 139XLR. I am going to replace the germanium diodes because they stock ones are only 4 years younger than me and I just turned 45! The Cobra 139XLR was the grandfather to the 142GTL. Includes alignment Kenneth R. On a scope I can see that the driver seems to be doing its job. The Dynascan Cobra company has a Service bulletin for the NO RX problem in this type of radios. I'll be putting the 449 on CL and using this for now on I think, it is just better built thats for sure. 19. I will post my results once done. 12 MHz and its reading 5. Owner's Manual Page 1 to 18 · Page 19 to 37 · Parts List. Get the best deals for Cobra 138xlr at eBay. com. Has the MB8719 PLL in this radio. Includes alignment Dec 23, 2018 · Out of the box, the Cobra 138XLR was one of the more capable Citizen’s Band (CB) radios available in the late 1970s, the heyday for the systems. May 14, 2008 · The TR5 is a high failure part in this radio. If desired, this mod may be wired through a switch. The 858 PLL was capable of 399 channels with four DPDT switches and some diodes across the terminals of the switches. The final, not so much. , Cobra Electronics;, build 1977, 1 pictures, 52 semiconductors, United States of America , schematics Kenneth R. The smaller the value, the more the receive is boosted. I am selling my Mobile Cobra 138 XLR mobile CB radio. Last modified 2024-11-04Cobra 138 (By Dynascan) SPECIFICATIONS May 7, 2020 · Today I found a great article on the Cobra 138 XLR which is funny since one just came into my hands this week! I've owned 3-4 of these over the years and always enjoyed running them due to their great on-air audio performance, and no hassle layout. This one has extremely low, as in less than a watt, output power. Oct 21, 2015 · Pretty stealth. Jul 31, 2008 · tp8 ch 19 showing 34. Here you will find instruction manuals, service manuals, user guides schematic, brochures etc. Jan 14, 2021 · Hello everyone, I figured I would post this issue, as I am sure there are a few of us with this model radio. Eventually I always drift away towards radios withToday I found a great article on the Cobra 138 XLR which is funny since one just came into my "PROOF" COBRA 29 LTD CLASSIC AM ONLY VERSION & AM/FM VERSION ARE AVAILABLE EVERYWHERE Beautiful Backyard Lakeside Jazz With Nature Therapy | Relaxing Music for Coffee Time, Stress Relief Cobra 138XLR Cb radio. It is an early Uniden u858 PLL radio. The old D858 chassis is a wonderful board to work CB and freebands with. Wire a single-pole, single-throw switch from pin 10 to ground (SW-2 on chart), and another from pin 11 to pin 12 (SW-1 on chart). I bought the sams manual wich made the recap much easier, the radio still had a couple issues and neded aligned so I sent it to nedlebender 35 Jon Beck I think he found 4 burned resistors and replaced them then did a great tune and alignment. But what gained the 138XLR a devoted following This document contains a list of radio modifications and tunings for various Cobra radio models. Includes alignment Receive Boost Modification Cobra 29 1. cbtricks. 7 volt. The styling is quite traditional but the performance is what sets this radio apart. This is the manual page for Cobra. The electronic store where I got Apr 6, 2005 · On the 138XLR, since the runs are shorter, Cobra just used regular wires coming from the Dynamike pot. Refer to the drawing on page 18 and locate pin 19 of the 858 PLL. 2046mhz. I have a Cobra138XLR that I bought new in the late 70s. Good price too. First 858 Cobra I ever had. 3. I did the mods guided by a good friend who past away If you have any SSB 858 Chassis, like the Cobra 138XLR, 139XLR original President Washington or Madison, Grant, Teaberry Stalker 202, Robyn 520D, 505D, and many other Realistic modelsThen this Mar 6, 2014 · What's the difference between Cobra's 138XLR & their 148 GTLl AM SSB CB Radio? Discussion in ' CB Radio Forum ' started by Holy Moses, Oct 24, 2014. The radio has extra channels. The Cobra 138 XLR is a large beast of a mobile – larger than most standard size CB radios such as the Cobra 148 or Galaxy 959 and it also has some weight to it as the case uses an extra bracket inside which you’ll see in my video. ) Editor: Les Jernigan Shop for Cobra CB Radio Replacement Parts and other quality products to keep you connected. I have a signal generator, VTVM, and solder/desolder Description: Original Howard W. Cobra 138XLR / 139XLR Owner’s Manual If you would like to help us put more manuals online support us. counter/clips and plastic alignment tools. Jun 28, 2025 · The 138XLR and 139XLR have the 858 PLL in it, so it is from 1977 or 1978. 148GTL-DX (Late) Don"t Ask Why? View and Download Dynascan Cobra 138XLR owner's manual online. This is your radio!www. When the transmitter is keyed, the LED will light at a reduced intensity, and will brighten a Dec 2, 2024 · O Using solid caps in place of regular electrolytics??? In Cobra 138XLR Onelasttime Jan 27, 2023 3 Jan 27, 2023 May 14, 2008 · The TR5 is a high failure part in this radio. Nov 22, 2011 · It is hard to navigate, but there is a lot of different information there for the 858 PLL board found on the TRC-458, Cobra 138XLR, 139XLR, and many others. J shop down under Click to expand would you happen to have the cb-126 for the Cobra 138xlr? Thanks in advance. Install a 22k-220k ohm resistor between these two points. *6 position rotary- will give 6 different channel Description: Original Howard W. no out of lock condition at PLL Chip ether. Diagrams Schematic Download COBRA 138XLR service manual & repair info for electronics experts. INC. com Someone who wanted to help you repair your equipment put together this information. Locate pin 14 of the PLL chip, and the Positive (+) side of C-12. See the images. Does anyone know where this information is available I'm finished Aug 3, 2011 · I plan on recapping them as well and giving them an alignment. I did pick up the 2. Hi all, just a quick look at the Cobra 138 XLR-A Australian 18 channel model. In 1993, the company name was officially changed from Dynascan to Cobra Electronics Corporation. Feb 13, 2023 · Replace your Cobra 138XLR or 139XLR bipolar final transistor with a high power MOSFET. 3- Red 4- Black Astatic (6 wire) 1- Shield & Blue 2- White 3- Red 4- Black Yellow NC Daiwa EM-500 Cobra CA Series 1- Shield & Black 2- Red 3- White 4- Blue Galaxy DC-521S (4 wire) 1- Shield 2- Yellow 3- Red 4- Black Galaxy CB-660EI 1- Shield & Black 2- White 3- Red 4- Blue Sadelta 1- Shield 2- White 3- Brown 4- Green Turner 1- Shield & Red 2 Disclaimer: Although the greatest care has been taken while compiling these documents, Nov 29, 2006 · Cobra 138 XLR by RedEye » Friday 8th Feb 2008, 14:03 Does anyone have the directions to unlock the clarifier? Thanks in advance! CBTricks. Thanks thats what I needed to know I have a freq. The radio works well overall now, aside from the receive having an issue. We have a great online selection at the lowest prices with Fast & Free shipping on many items! Dec 18, 2008 · Gentleman. Depending on your antenna height and how much amplification you use, you can expect anywhere from 50-150+ miles direct contacting, and when DX is right, all around the globe for DX contacts Description: Original Howard W. pdf Did you put in two 1n914 or 1n4148 as the Service Bulletin suggested? I used a 1N4148 in D2, and D26 a 3. com Vintage Advertising. And it works good. Database contains 1 Dynascan Cobra 138XLR Manuals (available for free online viewing or downloading in PDF): Owner's manual . About to try the mv1y Cobra CA Series 1- Shield & Black 2- Red 3- White 4- Blue Galaxy DC-521S (4 wire) 1- Shield 2- Yellow 3- Red 4- Black Galaxy CB-660EI 1- Shield & Black 2- White 3- Red 4- Blue Sadelta 1- Shield 2- White 3- Brown 4- Green Turner 1- Shield & Red 2- White 3- Blue 4- Black Yellow NC Cobra Main Index Radio Info Main Index CBTricks Home Page Mar 10, 2022 · Cobra Model 138XLR Owner's Manual Links Page 1 to 18 Page 19 to 37 Parts List Diagrams Schematic Diagram Schematic Diagram Technical Bulletins Technical Bulletin #1208 Technical Bulletin #1208A Technical Bulletin #1209A Technical Bulletin #1209B Technical Bulletin #1210 Technical Bulletin #1210A Technical Bulletin #1211 Technical Bulletin #1211A I emailed and talked with Toby and Mark and made a plan to have my Uniden Grant LT and Cobra 138XLR upgraded with the DDS VFO modules. Description: Original Howard W. I will get to it tomorrow after work. Jan 20, 2016 · Hi all, I am sure this has been asked before but I have a Cobra 139XLR (D858 chip), receive seems "decent" but it is somewhat noisy and I know I can improve the receive. In this case the radio came at my shop with a very low RX. In 1979 the 8719 PLL was used, and the radio became the 142GTL. The list covers many Cobra Description: Original Howard W. Rick. Aug 4, 2017 · Hi Everyone, So, on the bench is a Cobra 132XLR for an alignment. Supporters of CBTricks. Some of the stuff I have never seen, especially the continuous tuning dial with frequency counter. 11814 MHz. These amazing devices add extra frequencies, roger beeps, scanning, and more to virtually any radio and they also can solve issues with drift on radios like the Galaxy 959. 40-Channel Solid State Citizens Band SSB/AM Two-Way Radios. How to make Cobra 29LTD,Classics slide on TX & RX 1) Remove D-18 , R-110 , C131 and R-112. Here is a customers 138XLR that wanted the radio channeled and a freq counter added. Sep 3, 2018 · Among the many base stations, mobiles, coax, and meters, was a cobra 138. I have looked all over the web and I cannot find alignment procedures for a 1:32 XLR. Thanks. I went ahead and opened her up and cleaned it with some air and figured while I have the radio open I might as well peak and tune it, as I have done with just about every radio I have. I fixed one Cobra 139XLR today with the same problem. 055 MHz The Cobra 138XLR Vintage CB Radio with UFO is a classic mobile/in-vehicle radio unit known for its reliable performance With 40 AM and 80 SSB channels, this radio offers a wide range for communication. AND THE RADIO HAS TO HAVE AN ALIGNMENT . It starts with a frequency check (no adjustments. It will be is connected to ground by a very small land. I heavily modified it shortly after purchase. 9850 (based on alignment info for 139XLR posted on forum as I can't seem to find a service manual for this one) Checked voltage at tp7 on ch1 and everything is correct. We have a great online selection at the lowest prices with Fast & Free shipping on many items! What would the Cobra 138 xlr and the cobra 132 xlr put out if aligned properly. com Date Published : March 1989 Number of Pages: 78 Publisher: Doris Selman (Selman Enterprises Inc. 205mhz my radio read 27. It covers control functions such as DYNAMIKE, SQUELCH, RF GAIN, and MODE selection, as well as operating procedures for both receiving and transmitting. Includes alignment Aug 3, 2011 · Like so many things in life sometimes it is better to be lucky than good! I picked this one up pre-covid for under $140 with free shipping. 5A power supply, 2 of the hot swap locking brackets, the radio Get the best deals for Cb Radio Cobra 138xlr at eBay. If you would like to help with this project let us know. 3K subscribers Subscribe Nov 6, 2024 · I had a wild thought that if I added some resistance it might give me more of a gradual increase in volume vs. New member here. Pages are loose. I was just reading about the difference between the Cobra 135XLR and the Cobra 2000 in two separate "CB Magazine" reviews. 2) Put jumper were R-110 was Description: Original Howard W. 2024 Cobra CA Series 1- Shield & Black 2- Red 3- White 4- Blue Galaxy DC-521S (4 wire) 1- Shield 2- Yellow 3- Red 4- Black Galaxy CB-660EI 1- Shield & Black 2- White 3- Red 4- Blue Sadelta 1- Shield 2- White 3- Brown 4- Green Turner 1- Shield & Red 2- White 3- Blue 4- Black Yellow NC Cobra Main Index Radio Info Main Index CBTricks Home Page Nov 20, 2024 · VINTAGE COBRA 138 XLR 40 Channel CB Radio AM SSB Citizens December 25th, 2019 - VINTAGE COBRA 138 XLR 40 Channel CB Radio AM SSB Citizens Band 105 38 Used Cobra 138xlr Owned by Son in Law and used this CB for many years Has scratches on it from use amp wear around buttons see pictures for actual physical condition The mic has a chip off of the button to attach to mic bracket See last picture Description: Original Howard W. This operation manual provides detailed instructions on how to use and adjust your Cobra CB transceivers. There is a station A page which list's the modulation boosts and tune ups for the cobra range of radio's Apr 3, 2005 · Hi, all, I have a Cobra 139XLR (with the 858 chip) and when testing AM transmit I find the radio is a little off frequency. Today, Cobra CB radios continue to be produced. com paid for the hosting so you would have this file. You need to have Acrobat Reader version 5 or newer installed to view the files with icon. This model, powered by 12V, is a sought-after collectible for CB enthusiasts who appreciate the nostalgia and nnel tallqgon Units covered: COBRA 138XLR, 139XLR, PRESIDENT GRANT (858 PLO, WASHINGTON (858 PLO, MADISON(858PLL), ROBYN510D, 5201), REALISTIC -449, TRC-457, TRC-458 I. 1977 was the first year of the 40 channel radios. It turned out to be a bad final. Mar 9, 2008 · Hi loosecannon. Cobra Base Station CB Radios Cobra 93 (Discontinued) Cobra’s only AM Base with weather. It's looking for 5. The frequency alignment is a little different than most radios I have worked on. 2uf caps yesterday. 120+ channels, Add/subtract switch, open clarifier, peaked power spread through the channels. Good condition. I've already tried swapping out the final. com/radios/cobra/138xlr/graphics/cobra_138xlr_139xlr_tb_1210. pdf 562. Detailed instructions are Description: Original Howard W. the "no sound - jump to a preset level", nowhere close to the gradual gain experienced in ham radios or other CB radios, both modern (President Washington) and elderly (Cobra 138XLR). I will probably have time later in the day to get that intalled then will hopefully get some additional instructions from LC until I can get the freq counter. Includes alignment May 7, 2015 · Put on my bench and performed a complete alignment of radio using a 40 MHz scope and LogiMetrics 920-S101 signal generator, and a B&K 100MHz Frequency counter. SMIT INDICATOR (COBRA 138XLR). You then adjust L303 for 17. Includes alignment Cobra 148GTL ST (Discontinued) SSB Mobile with SoundTracker technology. If the files with or icon will not display see the for help on printing, viewing and using this information. Sams & Co. For example on Channel 20 which is 27. Find a comprehensive list of adjustments for Cobra radios on this page. MikesRadioRepair 35K subscribers Subscribe. Made in Japan, it features an automatic noise limiter (ANL) to enhance clarity. That looks perfect. When I acquired the radio, it barely put out any power. 6 KB · Views: 41 Theseus and Robalo Feb 1, 2009 · The Cobra 148GTL and the Grant XL both use the same board, and I agree with Unit 399, the Cobra 138XLR would be the better radio. Can anyone tell me what to align for receive or perhaps some simple mods. Includes alignment Just a quick video showing dial acceleration on a Cobra 138. VS4U! : - Radio Repair Books Service Manuals Radio MOSFET Modification Kits Repair kits Repair Parts Repair Services Calibration Service Alignment Service ecommerce, open source, shop, online shopping, store CBTricks. User Manuals, Guides and Specifications for your Dynascan Cobra 138XLR Two-Way Radio. Includes alignment Description: Original Howard W. I got with it a CObra CA-50 Mic which I mistakenly called a Ca-55 in the box, a Micronta 1. The modifications range from simple cuts or removes to more complex replacements of voltage regulators or other electronic parts. As you can see the freq counter and the 2 toggle switches. compatreon. Includes alignment Last modified 2025-02-11Cobra 138 XLR (By Dynascan) SPECIFICATIONS Mar 4, 2022 · Factory Service Manual Page 1 to 21 Page 22 to 39 Tech Note DIAGRAMS: Cobra 132A Schematic Diagram Schematic Diagram Chassis Wiring DIAGRAMS: Cobra 132B Schematic Diagram Schematic Diagram Chassis Wiring Mic Wiring Stock 1- Shield 2- Audio 3- Transmit 4- Receive Astatic (4 wire) Feb 8, 2025 · Factory Service Manual Page 1 to 21 Page 22 to 39 Tech Note DIAGRAMS: Cobra 132A Schematic Diagram Schematic Diagram Chassis Wiring DIAGRAMS: Cobra 132B Schematic Diagram Schematic Diagram Chassis Wiring Mic Wiring Stock 1- Shield 2- Audio 3- Transmit 4- Receive Astatic (4 wire) Find many great new & used options and get the best deals for Untested Cobra 138 XLR 40 Channel AM SSB CB Radio Vintage Transceiver Mobile at the best online prices at eBay! Free shipping for many products! Jul 6, 2014 · Yet another Cobra 138XLR. Includes alignment Cobra 138XLR / Cobra 139XLR MOSFET Upgrade kit This modification kit contains all the parts you need to install a MOSFET in place of the original bipolar transistors. Thanks The original Cobra CB radios were manufactured by Dynascan Corporation. Bundle Deals and fast shipping available. com Cobra Electronics (Dynascan) Radio IndexSee Icon Key at The Bottom of Page Cobra 138 XLR Citizen B&K Precision, Dynascan Corp. 7 volt Zener as one of the tech bulletins recommended reducing D26 down from 5 volts to the 3. by Rick » Tuesday 5th Jun 2007, 18:27 What is the output power on SSB? Did you check L43, L44, R179 and R199? What is the Base voltage at the Driver and Final, last time you gave me the Collector voltage. The red LED located above the channel selector is a proport onal output indicating device. Nov 18, 2021 · I hate to revive an old thread but all the advice here helped me bring my 138xlr back to life. 8850 instead of 34. Why do you keep putting my quote in your message, what is the point. In fact, Dynascan was responsible for developing the world’s first CB radio. I need cb 113 and cb 137. VCO and TX freq circuits an RX circuits tuned great. UPDATE: 11. Cobra 139XLR - CBTricks Cobra 139XLR Description: Original Howard W. Probably will not be using it much past my 138xlr. Apr 11, 2009 · Anyone by chance have the complete alignment info for both the TX and RX for the cobra 139xlr? the receiver on this radio is a bit numb and want to go through the whole thing. com/DXRADIOSHOP Description: Original Howard W. rpy 2zzvpd rwehi fm7 xk6qj fazrqb2 vik4qwp pd5 qod qpp2