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?? Frequency coversion -257 HP- need advice

All you need to do is remove the solder with a solder sucker and then add a small drop onto con2, you can probably take a small screwdriver and move the diode a small bit, it really isn't that big of a job, I have done 3 radios now and they were all 5 minute jobs. If you can't solder then take it to a tech, or you can google how to don the mod, cb radio magazine has a write up and photos to guide you. But like I said if you aren't comfortable with the job take it to someone that can solder it for you. Also read the owners manual, it explains that the diode needs to stay bridged between con 1 pin 1 and con 3 pin 1. Just remove the small solder blob in between con 1 pins and add a small blob onto pin 2 for stealth mode or pin 3 for expanded mode. I would personally just use con 3 unless you have a ham license and are planning on using the stealth mode features. I put all 3 radios i have touched into expanded mode and couldn't be happier. The magnum 257hp is one of those radios that people either love or hate, I am on the love boat as I bought one a few months ago and just purchased a 2nd one to put away for now. Next radio is probably going to be an RCI 2970N2. Anyway, good luck and don't think too hard or long about doing the solder bit, it's really a piece of cake.
 
222DBFL said:
All you need to do is remove the solder with a solder sucker and then add a small drop onto con2, you can probably take a small screwdriver and move the diode a small bit, it really isn't that big of a job, I have done 3 radios now and they were all 5 minute jobs. If you can't solder then take it to a tech, or you can google how to don the mod, cb radio magazine has a write up and photos to guide you. But like I said if you aren't comfortable with the job take it to someone that can solder it for you. Also read the owners manual, it explains that the diode needs to stay bridged between con 1 pin 1 and con 3 pin 1. Just remove the small solder blob in between con 1 pins and add a small blob onto pin 2 for stealth mode or pin 3 for expanded mode. I would personally just use con 3 unless you have a ham license and are planning on using the stealth mode features. I put all 3 radios i have touched into expanded mode and couldn't be happier. The magnum 257hp is one of those radios that people either love or hate, I am on the love boat as I bought one a few months ago and just purchased a 2nd one to put away for now. Next radio is probably going to be an RCI 2970N2. Anyway, good luck and don't think too hard or long about doing the solder bit, it's really a piece of cake.
Click to expand...


there is a guy on cgtricks.com that has a new in the box 2970n2 for sale for 340.00 shipped. good price if you are looking for one I noticed you said your next radio would be one. mod chip is already installed also.
 
9C1Driver said:
I think your gonna screw up a nice radio trying to be a wanna be tech. At least you voided the warranty at this point so good job. Now you can't complain when the radio is jacked up. That's my nickle worth and my opinion.


" I had no idea what the underside of the board looks like." That says it all right there.
Click to expand...

Well !!
I know this .... I'm afraid you are a little ahead of yourself on this occasion. Here are the simple facts,
and I will try to keep them simple:

1. Due to availability of the last run of 257s, Copper Elect. was one of the last places to have one.
2. Copper Elect. did no work on it. By the advice from others in this forum.
3. I was not trying to "save a buck", I was simply finding a unit in stock.
4. I tried to purchase from Bells, Custom CB, and others, but none of the ones I was aware of had any to sell.
5. I seeked out advice so as not to screw up a good radio, because I'm "not trying to be a wanna be tech".
6. Magnum International, a man named Eric, told me to look up CBTRICKS.com to see how to do the conversion. I am aware of several post here on how simple it is.
7. Your quote " I had no idea what the underside of the board looks like.That says it all right there". Was a simple reference to the fact that there was no need to remove the board to do the conversion, thus I had not seen it yet, to know if it would allow any more options.

Now can you offer any helpful advice, you haven't yet.
 
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Hey Sonoma, I saw that radio it's on a other forum as well, I have spoke with the gentlemen already but I am not sure now if that will be by next radio, I got to talking with some experienced old timers and got some good recommendations for what radio would be right for me. Thanks for letting me know though, if I were to buy a 2970n2 I a almost positive I would just buy it from Doug's custom cb' or Bells. 340 shipped is what is being asked and is a fair price for a new one. They run around 380-425 new. Think I am going into a different direction and give the alinco or yaseu radios a try.
 
Jumper Underneath ?

Ok back to my last valid question, would there be an issue of putting the jumper on the opposite side of the freq board ?
 
No as long as you remove the solder between con 1 port, don't forget to leave the diode in place going from con port 1 to con port 3. Then you can place a jumper on the other side of the board. I promise it's not that hard to add the solder in between the pins in con port 2 or 3 just get a small lump on the tip of your solder iron and place it onto one of the pins and let it heat up enough to go across the board and you are done. But either way, you still need to remove the solder connection on con port 1. Good luck and hope this helps. Don't be so scared man if you have ever soldered before you will be fine trust me, like unsaid I don't do soldering daily and found it to be a very easy job to do if you follow the instructions on the internet. Or the instructions given here are well. God bless.
 
Thanks again 222BDFL, I've done my share of soldering through the years, but not on circuit boards. And after the issue I ran into with that diode touching the con 2 pin, and then removing the board to look underneath, I was just concerned, it look doable to me. But if in doubt, I will ask questions, and this forum has been helpful. God bless.
 
Uncle Charlie said:
Well !!
I know this .... I'm afraid you are a little ahead of yourself on this occasion. Here are the simple facts,
and I will try to keep them simple:

1. Due to availability of the last run of 257s, Copper Elect. was one of the last places to have one.
2. Copper Elect. did no work on it. By the advice from others in this forum.
3. I was not trying to "save a buck", I was simply finding a unit in stock.
4. I tried to purchase from Bells, Custom CB, and others, but none of the ones I was aware of had any to sell.
5. I seeked out advice so as not to screw up a good radio, because I'm "not trying to be a wanna be tech".
6. Magnum International, a man named Eric, told me to look up CBTRICKS.com to see how to do the conversion. I am aware of several post here on how simple it is.
7. Your quote " I had no idea what the underside of the board looks like.That says it all right there". Was a simple reference to the fact that there was no need to remove the board to do the conversion, thus I had not seen it yet, to know if it would allow any more options.

Now can you offer any helpful advice, you haven't yet.
Click to expand...

All valid points, they are hard to find until Magnum makes more. I guess I should just read the forum after 11 beers and not type.....lol. The early magnums had soldering involved in the conversion, the last ones had that Con 1,2,3,4 deal and you moved a jumper. Looks like 222 has you all straight.
 
Just use a 30 watt iron if possible, make a small lump of it on the tip and place it on the con port of your choice in between the pins. When the solder sticks to the pins pull off and let it cool. Then hold the reset button for the CPU which is located on the underside of the board, if you take the board off and look you will see it, you can peek through the board with the radio held up as well and see it, a small black button, hold it for about 5-10 seconds then release it. You can also turn rv-4 as they have it listed on the schematic, up all the way, still helps the am modulation, this pot is located at the right don't of the board and is silver, all of my radios had them all the way up already but doesn't hurt to check it. then you can close that radio up and move to the mic. Take the mic apart and gently pull the circuit board out, you will see an orange pot that is variable, this is the mic gain for the microphone itself, you can turn this all the way to the right. I haven't had any issues with squealing or too much or too loud of modulation, I always get good audio reports, nice and clean as I am told. Do not try and turn the rfx-75 up any or hot rod the radio, it is set up pretty high from the factory, I installed a brushless fan on mine and it stays nice and cold now. And last but not least, make sure you have good power wire from the radio to the battery, use at least #8awg from the battery to the radio if in a Mobile and if on a base make sure to have a 25 amp power supply, if it's a mobile then you may want to invest in a good noose filter of at least 25amps as some vehicles don't have a good grounding system and this radio does produce a lot of noise from everything it can like power wires, other cars and a variety of everything that spews out RFI. Good luck and if you have any more questions don't be afraid to ask, I had to as well, radios have come a long ways even in the last 10 years man. You should be happy with the radio if you take care of it, don't bang it around and be mindful of the front knobs. It's a good radio for the price and I get nothing but good remarks from it and talk all around the world on a mobile with a sirio PL5000 performer magnet mounted. 73's and hope you get it all straightened out. God bless.
 
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Hi 9C1Driver,

I know for a fact that I couldn't read, or type, if I had eleven of my meds (Bud Light).
Offence was taken, I apologize, and now have forgotten.

Magnum is no longer making the 257HP, this is the Last of the Last. These are the ones that don't have jumpers.

Yes 222 has been, and I'm sure will be of any help requested.

May God bless you today, maranatha,
C D Vaughn
 
222

You have just made several good points, and I will have to study up on some.

My install will be mobile, and I have a question.

As to hard wiring .... it comes with a 14 awg polarized quick disconnect, with 15 amp fuse. Now my run to the battery is a little less than 9ft, and I was told that
10 awg was more than enough. So I found and ordered a 10 awg polarized quick disconnect with a fuse block,
that I will shorten to fit. So do you think I got bad advice on the 10 awg. God Bless
 

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