| Author |
Message |
    
Nvdoug
Junior Member
Username: Nvdoug
Post Number: 20
Registered: 2-2009
| | Posted on Saturday, March 27, 2010 - 2:06 pm: | 
|
Good Day All, I have a RCI2950(orange display) bought new many years ago. Friend talked me into putting a "Grandma Mod." to it many years ago. I sent the radio to the shop I bought it at to have some solder connections repaired, along with a tune & align. The radio seemed to work great & sounded great... But reports I received last night said that the radio has "backwards swing" What causes this and is ok to use???
Used as mobile in truck, cig. lighter plug pwrd, D104M-6B mic, Wilson 1000 mag mount in center of roof. After tune & align tech. reported: "dead key RMS 8.0w & PEP 18.0W"
Thanks for any info.
Doug
Northern Nevada
CEF#1019
|
Tech808
Moderator
Username: Tech808
Post Number: 17533
Registered: 8-2002
| | Posted on Saturday, March 27, 2010 - 5:43 pm: |
|
1st off I would suggest backing your Dead Key back down to 4 or 5 watts and then see if it still has a back swing.
There are several thing's that can cause this but that is the 1st thing I would suggest trying.
Also try turning the the Modulation setting DOWN and see if that help's.
If that does not help do a search here in the Copper Forum for the word's:
"backwards swing"
And you should find an question & answer dependaing on your situation.
Lon~Tech808
N9CEF
CEF#808
Radio Enthusiast!
|
Nvdoug
Junior Member
Username: Nvdoug
Post Number: 21
Registered: 2-2009
| | Posted on Saturday, March 27, 2010 - 6:43 pm: |
|
Lon~Tech808
Sir, Thank you, I will do the search. I did turn RF pwr. down to min. & the modulation down. The report was not as loud but still swung backwords. I'll still do some checking around. Thanks Again....
Doug
Northern Nevada
CEF#1019
|
Tech833
Intermediate Member
Username: Tech833
Post Number: 156
Registered: 12-2001
| | Posted on Saturday, March 27, 2010 - 7:47 pm: |
|
Hi Doug.
What you are calling 'swing' is actually an inverse proportion of positive peaks to negative peaks.
For an amplitude modulated (AM) transmitter to produce 100% negative and 100% positive modulation peaks (for overall 100% modulation), the positive peak needs to be about 4x the carrier power. In other words, if you had a legal CB radio that dead keyed around 3 watts, a 100% modulation positive peak would be around 12 watts.
If your radio is dead keying 8 watts, your positive peak needs to be at LEAST 32 watts. With a positive peak of 18 watts, your radio would appear to put out less power when modulated fully.
Your tech needs to try again. Although, from the sounds of it, I would suggest a different, more knowledgeable tech.
Your radio 'Mythbuster' since 1998
|
Nvdoug
Junior Member
Username: Nvdoug
Post Number: 22
Registered: 2-2009
| | Posted on Saturday, March 27, 2010 - 8:19 pm: |
|
Hi Tech833,
Sir, your clarification has helped immensely.
The Tech. reffered to has since retired...
I have just caught the radio bug after years off. Finding new contacts for reliable work are always a challenge out here in the middle of the high desert.
Thank You for your response.
Doug
Northern Nevada
CEF#1019
|
Dale
Senior Member
Username: Dale
Post Number: 1565
Registered: 12-2002
| | Posted on Saturday, March 27, 2010 - 9:21 pm: |
|
if ya have an external power meter hook it up
too it.turn rf power to 2 watts. then adjust
mic gain wide open.this should give ya radio
the [swing] ya talk about.if it doesnt then
id say its either mistuned or something went bad
inside radio
dale/a.k.a.hotrod
cef426
cvc#64
|
Nvdoug
Junior Member
Username: Nvdoug
Post Number: 23
Registered: 2-2009
| | Posted on Sunday, March 28, 2010 - 12:54 am: |
|
I do have a PDC600 meter I can hook up and see what will happen.
Thanks
Doug
Northern Nevada
CEF#1019
|
Tech833
Intermediate Member
Username: Tech833
Post Number: 157
Registered: 12-2001
| | Posted on Sunday, March 28, 2010 - 11:03 am: |
|
Doug,
If all else fails, you could contact Ranger and arrange to send your radio to them and have them bring it back to factory spec.
FYI- They have a factory spec for a reason. Yes, you can squeeze more from the radio, but at what cost? The people who designed that radio know it best.
Your radio 'Mythbuster' since 1998
|
Cactus_29
New member
Username: Cactus_29
Post Number: 9
Registered: 12-2009
| | Posted on Sunday, March 28, 2010 - 11:54 am: |
|
I would also check the cigarette plug and socket. It’s possible that you could be
encountering a current/voltage drop with the forward power swing. I would suggest hooking it up to a power supply on a base station with a good watt meter and perform some radio checks while inspecting your power output. Also you can try wiring up your radio strait to the battery in your vehicle. The reason I’m telling you this is I had a Kenwood 733 hooked up with a cigarette lighter plug once, and I couldn’t even get more then 20 watts out of it on the high power setting. I had wired it up to the battery to get the full 50 watts.
Just another avenue to think about.
Best Regards. |
Dale
Senior Member
Username: Dale
Post Number: 1567
Registered: 12-2002
| | Posted on Sunday, March 28, 2010 - 1:47 pm: |
|
catus is right try hooking it up to
a good battery or a power supply then
your watt mter and do some checking
dale/a.k.a.hotrod
cef426
cvc#64
|
Nvdoug
Junior Member
Username: Nvdoug
Post Number: 24
Registered: 2-2009
| | Posted on Sunday, March 28, 2010 - 11:32 pm: |
|
Gentlemen, Thanks for all the input.
I will hook it up to the base and at the settings that the tech. recomended which is RF pwr max & mic @ 1/3. But if I read the previous post correct. I would not want dead key to be that much higher than my positive peak when talking. I will do some checking with the settings as reccomended, and see what kind of reports I get.
I probably got confused. Because all that I have read. To me it seems the radios that are bought brand new have a tune & align job done to them before they are even shipped, or they have the clairifier opened up, or what have you. So I thought that was the norm. Which I thought would take the radio out of factory specs., as they should be good to go being new in the box..
With time and your patience I will figure it all out.
Doug
Northern Nevada
CEF#1019
|
Tech833
Intermediate Member
Username: Tech833
Post Number: 159
Registered: 12-2001
| | Posted on Monday, March 29, 2010 - 11:11 am: |
|
Hi Doug.
We are here to help!
The problem with the 'align and tune' package is that they shorten the life of your radio. let me explain.
To keep this simple, let's just study the final amplifier section of your radio, in this case, the final transistors. Transistors have safe operating parameter specifications that are determined by the manufacturer. Those specs are not some arbitrary figures, they are from testing. If your radio has a set of transistors that can safely operate at 20 watts output, that doesn't mean that's all they can do. If you exceed the safe operating specs, you can get them to produce more power. But, if that is true, why doesn't Ranger send their radios from the factory already 'tuned up'? Because the radios will fail prematurely. It IS in a tech's best interest to have your radio fail! Then, you will have it worked on again. It is NOT in the best interest of the manufacturer to have your radio fail, it affects their bottom line (returns) and reputation.
If it was safe to have your radio peaked out to 40 watts, don't you think Ranger would send them out that way? It would be a great selling point to say your radio does 40 watts instead of 20 watts, right? It makes no sense for the manufacturer to purposely de-rate the output of a radio when they make their money from sales. Some 'tech' comes along, charges you money and magically 'peaks' your radio, and you're happy... Until it fails. The 'tech is happy because he/she made money off of you. Even when it fails, the tech makes more money from you. It's a win-win for the tech. So, it is in the best interest of the 'tech' to squeeze as much power out of your radio as possible, despite the shortened lifespan of the radio.
Also, 99.9% of the CB 'techs' do not have the equipment to accurately align a receiver. They just crank on things and listen for this or that. That is NOT aligned. The factory does have the proper equipment to align your receiver, and that is important to interference-free operation.
Your radio 'Mythbuster' since 1998
|
Dale
Senior Member
Username: Dale
Post Number: 1569
Registered: 12-2002
| | Posted on Monday, March 29, 2010 - 9:44 pm: |
|
yes doug keep rf power at 2 watts and mic gin
all way up.[note] be sure to turn correct one
as these are combined on 1 knob .should see peaks around 8 watts.give or take.most radios
dont come with open clarifers.i know magnums
do and ranger [rci] dont
dale/a.k.a.hotrod
cef426
cvc#64
|
Nvdoug
Junior Member
Username: Nvdoug
Post Number: 25
Registered: 2-2009
| | Posted on Monday, March 29, 2010 - 11:28 pm: |
|
Tech833, Thank You for your explanation.
Dale, I will hook everything up the base, with my meter inline. Adjust my settings and listen for the reports I receive... & ck my pwr swing.
Thanks Again
I have a question about my antenna. If I do not see it previously discussed I will post it.
Doug
Northern Nevada
CEF#1019
|
Keithinatlanta
Advanced Member
Username: Keithinatlanta
Post Number: 864
Registered: 3-2003
| | Posted on Tuesday, March 30, 2010 - 8:46 pm: |
|
Hey Doug. As you can see from above, there are a lot of smart people in electronics that are on this forum. And they know their stuff!! That is what I enjoy after all of these years, is getting education from these folks. Sometimes they are over my head, but that is because of the knowledge they have in electronics. But I love it, because I "learn" from them. Good luck on getting the radio to specs.
Keith in Atlanta
CEF 150 |
Nvdoug
Junior Member
Username: Nvdoug
Post Number: 28
Registered: 2-2009
| | Posted on Thursday, April 01, 2010 - 12:43 am: |
|
Thanks Keith,
Thats the Amercian Way, Right !!!
Helping Others
I will post results after I do tests as per recommendations
Doug
Northern Nevada
CEF#1019
|
Starface
Senior Member
Username: Starface
Post Number: 2770
Registered: 1-2005
| | Posted on Thursday, April 01, 2010 - 12:51 am: |
|
I can only say I wish the East Cost had Paul too.
Doug, Get the radio back to manufacturer spec.
There is nothing like working QRP ( Low Power ) and working a state across the country or work a country across the pond with 4 watts.
Everyone is trying to accomplish something big,
not realizing life is made up of little things.
|
Keithinatlanta
Advanced Member
Username: Keithinatlanta
Post Number: 866
Registered: 3-2003
| | Posted on Thursday, April 01, 2010 - 11:53 am: |
|
Hey Starface, I will 10 - 4 the comment about using 4 watts and talking across the country!
Did I hear someone in the background say "antenna"? 
Keith in Atlanta
CEF 150 |
Nvdoug
Junior Member
Username: Nvdoug
Post Number: 29
Registered: 2-2009
| | Posted on Thursday, April 01, 2010 - 7:38 pm: |
|
Well I ran straight pwr from the battery to the radio. The freq. counter light does not blink when I talk now. On the base equip. I adjusted RF pwr all the way down, and the mic gain to 75% on both mic and radio. I saw 4w dead key with a swing to 16w at the peak of a whistle.
With radio back in truck @ those settings the reports were good. With forward swing to boot.
Running straight pwr helped I'm sure. But I believe the major was running RF pwr too high. As backward swing returned when RF pwr was cranked back up. All settings returned and all reports were good once again.
My Sincere Thanks to ALL who helped the Rookie out and gave some input.
Doug
Northern Nevada
CEF#1019
|
Dale
Senior Member
Username: Dale
Post Number: 1570
Registered: 12-2002
| | Posted on Thursday, April 01, 2010 - 10:13 pm: |
|
glad it all worked out for ya doug.those are decent radios
dale/a.k.a.hotrod
cef426
cvc#64
|
Starface
Senior Member
Username: Starface
Post Number: 2774
Registered: 1-2005
| | Posted on Thursday, April 01, 2010 - 11:08 pm: |
|
Doug, Glad it all worked out for you by powering the radio from the battery.
A great source of direct power.
Now as for whistle into the mic, NOT GOOD, should always talk into them in a normal tone of voice,
Here is the reason why and what you can do:
To whistle into a microphone clearly, you need to eliminate "wind-noise" from reaching the mic's diaphragm. Firstly, try to use the mic "off-axis" or diagonally, so you are not blowing directly into the business end. Secondly, you can cover the mic with a foam windscreen. Lastly you could also try a "pop-filter" or "pop-screen" that cuts breath bursts even further. You can make one by stretching a nylon panty-hose on an embroidery hoop, or a wire coat hanger bent into a loop and placed between your mouth and the mic. Cheaper microphones may not be able to handle some of the frequencies of whistling and cause it to distort as well. Something to think about.
Everyone is trying to accomplish something big,
not realizing life is made up of little things.
|
Cactus_29
Junior Member
Username: Cactus_29
Post Number: 10
Registered: 12-2009
| | Posted on Friday, April 02, 2010 - 2:23 pm: |
|
Nvdoug,
I’m glad you got it squared away.
Using a Cigarette plug with your power turned up to high was probably most of your problem to begin with. Most dual final radios and larger require a constant 13.5 to 13.8 volts to operate properly specially on ssb. SSB Wobbly voice on transmit in conjunction with heavy dimming of the display lights is mostly contributed to low voltage at the transmitter. Always make sure your positive and negative wires have clean solid connections to its power source with the proper rated fuse in a fuse holder that’s in good condition. I have found that more then 50% of the time, electronic malfunctions are from poor continuity. I’m glad everything worked out and 73s to everyone, Good Job
Best Regards... |
Nvdoug
Junior Member
Username: Nvdoug
Post Number: 30
Registered: 2-2009
| | Posted on Friday, April 02, 2010 - 8:25 pm: |
|
Hey Guys,
Thanks for the replys.
NO MORE WHISTLING into the mic..GOT IT..THANKS..
I like good connections as well, and for years, on everything I do thats electrical. I have always soldered & shrink tube wraped..
I put a 10amp fuse at the battery, and radio fuse at the radio.. I will put it all to the test tomorrow... 10 hr road trip !!
Happy Easter to all & THANKS once more..
Doug
Northern Nevada
CEF#1019
|
