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New to forum: help with Rfx (photos included)

I switch out the final in the rfx75. Same stats.... do es any one think it could be the swing mod I did?
 
Which instructions are you referring to? The one on cb tricks says to remove j36 and replace with 1000uf cap with small resistor (33r) on the bottom... this IS the swing mod am i correct? This radio was brand new when i installed so all mods were from the instructions.
Please understand I'm not arguing, just trying to make since of all of it.
 
Ya, i just laid the wire down and soldered it to the lead of the other component. Nothing was near it so i let it all hang. This is where the signal comes back on board. Would somthing like this get through the solder mask?

Of course. Why would you let the excess wire drop onto another trace and risk it shorting between the two?????? Makes no sense to me but it's your radio. :confused:
 
Which instructions are you referring to? The one on cb tricks says to remove j36 and replace with 1000uf cap with small resistor (33r) on the bottom... this IS the swing mod am i correct? This radio was brand new when i installed so all mods were from the instructions.
Please understand I'm not arguing, just trying to make since of all of it.

Yes; adding an electrolytic cap there and a resistor underneath the board is the swing mod for this radio.
Just reverse what this page shows:
Cobra 29 LTD super modulation modification

EDIT:

After re-reading the RFX instruction sheet myself, you are quite right!
For this radio installation, they tell you to put a swing mod in.

My mistake. After reading all of the other RFX instruction sheets for other radio models - they all said to take any swing mod out. But for this radio, they want you to put one in. You had it right in the first place!
 
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Best thing to do is remove that POS RFX 75, restore the radio to stock, and just run a kicker behind the radio. I had one on a Cobra 29 and never could get it to work right....
 
The LX seems to be mosre sensitive to SWR and the NECESSITY for extra or proper grounding. Both LX's have problems and the other 5 radios(148's,29 &2000) do just fine on the same antenna. I kept flippin out and bugging everybody on the net trying to figure out the LX, the SWR pot ( it needs proper adjustment) just like the YT video. the extra power will make the SWR problem arise. Atleast it did in my case. If you turn the pot full C-Cwise and then back a hair like the C-CB video mine is at 2.6-7....
There is also a TSB regarding the COBRA problem with the LX. Both the LX's hear did more than just adjust the alert light.
When you watch the video, it sure seems there is alot more proper setup and fine tuning needed (with bench equip) to get these LX's to work with the rfx....jmo....of course
Looks like your on the way to blowing up the 10 radios and still not figuring out why......I'm not sayin'...I'm just sayin'



Which directions said to use the swing chop??
Good luck and go slow you will figure it out...if your methodical and PATIENT
The 29LX schematic has 23 miss marked components that I found so far, mostly resistor values and E-cap values or even completely missing like C35,41,43,44 R41,500, alot of RX section stuff
 
I have noticed the deal with the swr as well. I tIsought it was my setup. Because everything isn't well setup. By my other 29 has similar swr issues with just the Mosfet. Can some one Explain the trim pot used for antenna warning? is it sensitivity? I'm not giving up here bc the whole point of this is not to have abad ass radio.. Just learning experience
 
That's what I'm saying. I can't seem to get the swr down on any channel.. i haven't been able to fully modulate freely yet for fear of blowing out up. Already changed the final in the rfx75 once lol. I seem to have trouble ground antennas anyway. Any one got any good tips for ngp antenna on trucks.. while I'm at it
 

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