President Mc Kinley Modulation Probs

Hello everyone

I have purchased this radio a couple of months ago not wide banded. All worked fine, but with quiet modulation. so a brought a KPO power mic NM-532. 
Which did help . I then wide banded the radio after a few YouTube videos on how easy it was to do and  get few extra logs on the fire as they would say. All good for a while a few weeks , now when i choose SSB the modulation in upper or lower it  goes mental , totally unusable squealing all , over modulating you name it. The modulation works fine on FM & AM  . 
I have tried all sorts of combinations with mic gain up and down with power mic and stock mic , power lower or  higher . 
I was going to send back but I have opened the radio up and voided the warranty . 
Can anyone make some suggestions on what I can try or should I just find someone to pay and get it tested and fixed . (if anyone knows someone that would be great).
I am quite confident with soldering and tinkering if that helps but with testing equipment etc. No No .
Sorry to be a pain . Thank you for your time and effort.

Regards John  CT4515.  Newbie  

Hope to catch you on the sometime soon :D:D

how do you know your modulation is bad ?

Hello  BASS 666

I have tried the radio from different location to get further contacts and from home to another radio. Everyone I have spoken to on air has reported it . 
Hope this helps 

cheers John

ok mate .. i thought you were going to say it sounded bad using talkback and i was going to tell you mine sounds bad on talkback but is clear as a bell going out on air ...

BASS 666 wrote:

how do you know your modulation is bad ?

I can confirm John's Modulation is terrible on ssb but on fm it's fine (R5) but quiet.
I think I have a recording of it, will post it tomorrow if I have.

Can't get quiet modulation on SSB, if the audio level from the mike is low all that happens is you transmit less power.  You can get over-driven horrific distorted compressed mush that sounds louder but it's the compression making it appear it is rather than it actually being so.

What power supply do you run it from.

Some good suggestions already made for you there John as well as informative pointers.

If everything was working fine but now not and even changing back to the standard mic doesn't alleviate matters then obviously something has gone wrong. (Obviously. )

It'd be worth checking your whole setup before doing anything else....


Are you running mobile?

If so it'd be worth checking your power connections as well as your coax for any pinches, kinks or otherwise deformations. If you have a mag mount give that a check too - it could well have swayed in the wind so much or received enough rainfall to ruin a connection. That'd make your whole setup an antenna including the radio, the mic, even you(!) and feed RF back into the radio making it 'squeal' or distort.

If homebase then see if you can perform similar checks and pull out the old SWR meter to make sure something isn't amiss on your antenna connections. (Many can't terminate a PL259 properly and neither can I with poor Chinese mass produced pressed junk connectors!)

As suggested by Alan and seen just recently on the forum check and re-check, then double check your power supply. If it ain't producing enough current or even have RF sensitive electronics (which it shouldn't if properly designed for radio use) it'll be fine on AM/FM but show problems with SSB. Although that should have shown up sooner unless something is amiss with it now.


What about your wide-band mod?

You say that you're handy with a soldering iron (after all it isn't that difficult - you shouldn't hold it at the hot end ) but I've seen on more than one occasion small 'balls' of solder rattling around in a radio after a 'mod'. Doesn't take much to move the radio and have one 'roll' into somewhere it shouldn't!


We can only offer suggestions and advice from afar which may or may not help. Just make sure you never shoot the messenger.

If all else fails the you'll have to fork out to have the radio a 'proper' good look at. It's just getting harder nowadays without the local 'whizz-kid' around the corner or local rig 'doctor' that used to abound back in the day.


There may even be something that you've inadvertently overlooked and not told us about (which happens) so worth checking everything else, including radio menu settings.


I wish you the best of luck with it all.

73's
Victor

Tonyvic wrote:

BASS 666 wrote:

how do you know your modulation is bad ?

I can confirm John's Modulation is terrible on ssb but on fm it's fine (R5) but quiet.
I think I have a recording of it, will post it tomorrow if I have.

I found the recording but I bet John doesn't know what he altered between the first and last part of the clip! (The last 15-20 seconds is about the best I have heard even on the many tests that we have done with just the two of us).
Johns Audio

Now that is bad.
Never had a sound like that before.

Wow!   That's a little bit more than 'squeal'.

Sounds like the limiter circuits are kicking in shutting down the output. (Over driven.)

(Unless I'm seriously mistaken and maybe Tony was using too high a 'squelch' on his receiver or the recording was over driven.)

Have we "been-a-tweaking" at all?

I presume it's the new McKinley?

They do seem to be a favourite to dig out the multiple reading specs + magnifier along with the golden screwdriver. I've heard tell that apparently President, despite years in the industry of designing, manufacturing and selling CB radios, set the 'levels' too low at the factory.

Maybe it even came 'peaked-and-tuned' which seems to be a favourite amongst certain re-sellers.


John, you've either got something seriously loose on the audio path, over driving with the KPO or maybe even 'twiddled' something you really shouldn't have.

I'm sure there's even been "twiddling" mentioned here at CT before.......

Ah, found it :-

https://charlietangodxgroup.forumotion.com/t9-president-mckinley-eu

Twiddle-twiddle!



If you have then there is the choice of the service manual, (wonderfully provided by SimonTheWizard) :-

https://simonthewizard.files.wordpress.com/2019/04/service-manual-mc-kinley-us-12-24.pdf

The favourites would be RT202, RT203 & RT206 plus you'll need some basic test equipment....

or twiddle and pray but best otherwise to get the services of a good tech involved.


Don't worry, I'm not accusing you of 'twiddling' (did you?) but know that often these can come 'pre-twiddled'.

Let's hope it's not the above and simply a case of a loose connection or some such.

But some things in CB never change with the passage of time and that proverbial golden screwdriver hasn't half done the rounds.
(Along with bunging power-mics on everything.)


I hope you get sorted mate.

All the best,
Victor


(Not all of this was written for any person in particular although in an attempt at helping the OP John. Mainly because someone else may read this posting further in the future and perhaps glean some useful info. Forums can be handy for that.)

Victor, first off congrats on the promotion it's well deserved.

Victor wrote:

maybe Tony was using too high a 'squelch' on his receiver or the recording was over driven

ME ,
I didn't alter the squelch and you can hear the much weaker station and Ray(Razz229).
I agree the recording is a tad over the top.

No worries there Tony and a huge help with posting the recording so well done.

Believe you me that was a much better recording than most I've heard!
(I've given you a 'thanks' as such too.)


Just hope that John can get sorted out and I know I was probably pre-emptive with the 'twiddle' commentary but I've seen inside a lot more radios than I care to remember usually accompanied with a guilty looking face from the owner.


Stellar input to the forum as usual there Tony, you keep well and keep enjoying your radio.

Tonyvic wrote:

Victor, first off congrats on the promotion it's well deserved.

Victor wrote:

maybe Tony was using too high a 'squelch' on his receiver or the recording was over driven

ME ,
I didn't alter the squelch and you can hear the much weaker station and Ray(Razz229).
I agree the recording is a tad over the top.

Now you have started something Tony.

My audio doesn't sound as good as it could be, unless I had just finished talking to that station that was 5k or more off frequency! (thank the radio gods for a clarifier)

Ha! Ha!

Ray, I've scanned the CB frequencies on many occasions with both my radio or the online webSDRs and at times it looks like most are working 'split'!
(Twiddle - Twiddle)

Any audio reports will always depend on how much of a 'pal' you are to the other operator.

That's true for CB or Ham radio.

(Unless you have a new YaesuIcomKenwood whatever then you need to go into menu option blah-de-blah and adjust your top a little by adjusting blah-de-blah, with a tweak of compression blah-de-blah....)

Hello everyone

Sorry for late reply be a little busy..

Thank you for all the suggestions and pointers I will definitely recheck.

Just a few things that have done as follows :-

Power wise have been on a fully charged leisure battery  Yuasa L36-AMG 95Ah for when mobile, a 15Ah power supply in shed and a 30Ah supply in house with all the same results.

Changing option in menus Etc. and on mic, with no luck.

I have swapped to home base antenna 1/2 wave silver rod . which I use with my Yaesu and no change in modulation .

Used a new mag mount  on car and a home brew 2tl2 home and mobile.  

When I wide banded the radio it meant cutting a wire move a jumper pin , that's all no soldering involved . 

As I had mentioned earlier about tweaking , it was all about the settings and menus I could change. Reset the radio and try again . 

I would never put a golden screw drive into it  not even a platinum one.  so no variable pots have been tweaked inside nothing at all. 

I have done my best to keep things  clean when I opened the radio.

With all this said I could of done something  but with no intentions  we can make mistakes.  but I don't understand .

Sorry to trouble you all with my dilemma  , I just hope its not an expensive lesson learned .

hopefully this will give you a little more insight to the problem and the things I have tried.

Once again thank you all  for your input and suggestions.

No offence was taken with what could  happened in the comments , I am just really struggling with what to do now.

Hope this finds you all well and on the air DX ing .

Regards John 

26CT4515.  73s

Hi John,

Firstly, I profusely apologise for my presumptuousness. 

I'm to much of an old fart and witnessed too many decades of CB twiddling that I tend to presume the worst.

Not being on my laptop instead currently relegated to my android tablet I can't do a lot of searching for you at this moment. However I do recall the mod now that you've mentioned it requiring the "simply snip the wire and move the jumper" thing. I seem to recall that this increases the power output too and therein may lay the issue in that the radio would require readjusting it obviously being originally factory set for its intended use.

I had a quick search of the forum and it does appear that this may be the case :-

https://charlietangodxgroup.forumotion.com/t1753-help-with-president-mckinley

I'm not sure if Conor (Northern Crusader) resolved his issues but couldn't find any further entries here at CT.


However, what concerns me is that apparently you performed the export modification and you say that everything was working until more recently(?) This sort of goes against the grain of what I was thinking in that the radio would have to be set up specifically for export mode.
(It turns out suppliers who provide this mod also make the adjustments necessary as you would expect - Knights being one such example.)

It seems to be a popular modification judging by views on videos and I would have thought that more people would have mentioned if they'd had issues after performing it.

If the RF power output does jump by this fairly significant amount after modification then it may point out other issues you may not see otherwise. Such examples would be poor terminations on coax patch leads etc. with any sort of SWR protection or other circuitry shutdown kicking in earlier. Poor PL259 connectors can and do have connectivity issues especially to the braid shield and why I tend to use compression fittings. More RF power would also be reflected back to the radio if your SWR is poor and will tend to be more of an issue in SSB modes due to the peak-power nature of transmission.


I'll do some more searching for you John when I'm able but unfortunately it won't be today due to other plans and family commitments.

Might be worth double checking your setup especially with something in common on every configuration you perform such as that 'favourite' or only patch lead.

Otherwise you may need the services of a 'tech' to check over the radio and perform any calibrating/setting up required.

Unless of course any other helpful member here at Charlie Tango has first hand experiences on such issues and can provide you further help.


I'll catch you further down the line and wish you all the best,
Victor

Sounds to me that it needs a set up after the "conversion" 

I guess your options are to contact the company you purchased it from, or if they dont do set up see if knights will do it for you, I dont know much abouth Knights but they seem well regarded and appear to have the skills and tolls to sort it out.


edited to add, based on your description of cut the wire to "wideband" it worked ok for a while then when on the fritz and assuming it is a faairly new radio it could well be a component failure causing the issue as it is one side of the bathtub curve for things breaking in that it is more likley to fail when new then fails drop off and increase again as the device gets to end of life.

Hello everyone.

Once again thank you for all the support , suggestions ,pointers Etc.
It has been very much appreciated  to no end.

Just a very good update for solution .Hopefully:cheers:.

I went back to the beginning and checked all wires ,coax ,power on all three types. (30Ah 15Ah 95Ah leisure battery) All good.

I then got a usb plug in micro scope and went over circuit board on both sides and found a dog hair between Parts on board wedged in so removed it,

totally carefully desoldered the loop wire  that you cut for wide banding, with solder wick , sucker etc.

Then put compressed air  through out the circuit board to remove any final junk.

Put the radio back together and factory rest.

Now for the test . 
I did some recordings in SDR Uno with different settings power , mic gain radio and power mic with some very good results.

I then went mobile and had a chat with a fellow operator who reported a much better audio like from squealing to a radio 4-5..

So some where in the mix of it all I think it may have worked. So on this coming Thursday I will head up high and get in to the southern  and southeast net with Ray CT2290/CI2290 
and fellow operators and see how we go.

Thanks again Everyone most helpful.

Regards John  CT4515. 73s

great news glad its fixed and my doom laden theory was wrong.

Hi John,

Glad that it seems you are back on track and operational again, I hope that continues to be so in the future.

Apologies for not getting straight back to you but what searching I did turned up nothing amiss with anyone that had modified their radios. (Maybe your factory reset was part of the solution?)

Have fun with it all.  

73's
Victor

Hello Everyone

Thank you to all.

Hopefully is was a human error on my part. Time will tell on Thursday.
Any suggestion that where made by any one even if they were not right it still helps the thought process to get to the winning post.

Much appreciated .

Regards John

yes i seem to be having quiet modulation problems at the moment someone was having trouble hearing me last night 

Hello Everyone

Hi skyrider  in the end I had to turn up the modulation myself in the rig , I was very hesitant to do it but with a lot of help and suggestions from friends on here and on air especially Nicky Ellis ,I managed to sort it with great reports. If you need me to tell you the process I went through just let me know but it was very easy in the end .
Regards John

Hi John, I’m curious to know how you did it.