HR2510 swr issue

[Watergate]

I just bought another HR2510 locally, I needed another hole in my head apparently, at least according to my wife.

Anyway, I hook up the radio and start checking it out. Power is fine, 10 watt dl swing to 38 watts. I hooked it up to my antenna, which I know the swr is good on. 1.2:1 and 1.3:1. That has been checked with an external meter. However when I checked the swr with the radio, it pegs the meter. So I hooked up my external and checked it again. Same as its always been. 1.2:1 and 1.3:1.

When I check the swr with the radio's meter, with the external meter in line, it shows the same as the meter. Or as close to it as the digital meter can. Unhook the external hook up the radio direct to the antenna, and it pegs the meter again.

I tried hooking up the 2510 I just bought from cottentop on this site, it reads normal. As does a few cobra 29's I checked after that. So I'm thinking it has to be the radio itself.

Any suggestions on where I should go from here?

Sent from my DROIDX using Tapatalk

 

[RatsoW8]

Are you calibrating the meter first before reading the SWR scale? If you are then the meter may need to be re-calibrated internally. The service manual for the 2510 is available on CBtricks.com.

 

[AudioShockwav]

This is going to sound weird, but pull the cover off and look to see if there is a Mica insulator behind the final.
If there is not a insulator, unbolt the final, clean off the old heat-sink compound behind it.
Then re-install the final with a new insulator, and some fresh heat-sink compound....you do not need to go crazy with it, just a thin coat on both side`s of the insulator.
The next thing to check is on the bottom of the Main board, there are two small caps ( c124 and c125 on a Hr2600), They are soldered across the final at the rear of the radio, you can remove them.
Both of these have been known to cause weird SWR/Meter problems with the 2510/2600 radios.
http://www.worldwidedx.com/export-radios/131209-hr-2510-rf-meter-problem.html
This is Assuming everything else is working properly.

Another thing to note is that these radios are getting old, and caps start drying out and failing, along with the known glue problem.

73
Jeff

 

[AudioShockwav]

Some other issues with these radios.

http://www.worldwidedx.com/export-radios/59817-lincoln-hr2510-defective.html

http://www.worldwidedx.com/general-cb-services-discussion/72064-president-hr2510-troubles.html

I really like these radio,s and in the past highly recommended them, but it has gotten to the point in time now that if you get a 2510/2600/2830/Lincoln radio, you almost have to expect to do some preventive work on them.
The Last run of Lincolns that used the MRF455 as a final are the youngest of the series and are still holding up well, but the older ones are starting to show there age.
The Glue is a problem because it dry`s out and can become conductive and cause hi resistance shorts, it can eat up some of the fine traces on the CPU board were it is used to glue the voltage regulators down.
The electrolytic caps are old, and they dry out, change value or short.
The Main board was developed back in the 80`s, if you look it probably has UNIDEN 1988 silk-screened on the board.

Good radio,s just have a few known problems.

73
Jeff

 

[undertaker]

Yep still got my Doc tuned lincoln!!!!!

 

[Watergate]

Yeah, these are awesome radios, I know they are getting up there in age, that's why I own three of them now. And one of them is currently spending some quality time with the guru, Rogerbird.

I'll check out the final and see if it has its insulator, and check the caps on the final tonight. Thanks for the help.

Sent from my DROIDX using Tapatalk

 

[freezy]

Hello New Guy here . im in the wrong thread

 

[Se7en]

Just a guess here is the radio maybe keying on another band other than 10m ?

★ Sent from my Droid★

 

[Watergate]

Nobody would ever use a 2510 for out of band transmission, would they?

 

[Se7en]

Nobody would ever use a 2510 for out of band transmission, would they?

Toughts
Transverter on board?
Maybe Magical screw driver used inside.
Maybe radio is tx on 11m maybe 12m..?
Bad vxo?

Sent from my Xoom using Tapatalk 2

 

[Watergate]

Must be just plain old bad alignment. Every time I try to transmit on 28.425 usb, It seems to magically start transmitting on 27.385 lsb.

Although the insulator behind the final cleared up my meter issue.

 

[AudioShockwav]

Every time I try to transmit on 28.425 usb, It seems to magically start transmitting on 27.385 lsb.

Pull the cover on the radio, and look at the crystal number X302, this "should" be a 22MHz crystal, chances it has been changed to a 20 MHz crystal.
This will cause the radio to TX/RX 1 MHz lower than the display reads on the radio.
Replacing the Crystal will put the radio back up in the 10 Meter band, if that is what you are wanting to do.
To expand the TX/RX and still have the correct display, replace the crystal for the proper one ( 22 MHz) and follow the instructions found here.
http://www.cbtricks.com/rogerbird/2510/conv.htm
This will allow coverage from 26.000 MHz to 29.699 MHz (Some radios will go to 29.999 MHz).
Just in case you need to use the radio as an IF for a transverter for 2 meters or to be able to monitor frequency's outside of ten meters.........


73
Jeff

 

[mr_fx]

suck thing is you are going to need to realign after replacing that crystal. also I would make sure those crystals check out in spec while you have the radio open

 

[Se7en]

Sounds like a lot of work, id try to get my money back and buy one from someone else and test it before you if you can.

However if your up to doing all this work to the radio atleast you'll know it works correctly cause you did the work.

★ Sent from my Droid★

 

[Watergate]

Thanks for the help gentleman, but by bad alignment, I was referring to the operator.