Connex 3400 HP problems

[trucker]

Final update, the 3400HP is alive and working well. FINALLY !!
How long it will last, is anyone's guess. The bad voltage regulator
nailed several other parts, including one of the finals, (had both replaced
as I feel it's better to have a fresh, matched set) and the trimmer, and three
other capacitors in the BIAS adjustment section for each final. Now, the BIAS
voltage stays steady at 3.2 volts on each final. The only complaint I have is the
talkback is super sensitive. With my Connex 3300HP, I can have it on and hear
myself clearly without any squealing feedback. With the 3400HP, just turning it
on and with the mic gain about half way, it squeals. Turn the mic gain below that
and it goes away. And I cannot hear anything on the talkback. Don't really need it
but, it is kind of nice in a way. Otherwise, everyone that has heard the radio says
it has plenty of punch in the audio and is LOUD. (using an Astatic 636L)
Just hope it lasts a while. I'm keeping my 3300HP as a backup. Several of the guys
at work want it. ................Not happening!!
trucker

 

[Robb]

It's a MOSFET output. Soooo . . . keep it running cool, don't run it all of the way open, and keep an eye on the SWR. From what I've read, MOSFETs don't tolerate poor SWR's like bipolar transistors do.

Congrats!

 

[trucker]

It's a MOSFET output. Soooo . . . keep it running cool, don't run it all of the way open, and keep an eye on the SWR. From what I've read, MOSFETs don't tolerate poor SWR's like bipolar transistors do.

Congrats!

Thanks! I have been keeping a close watch for heating on the case. So far,
it has run cool to the touch. (well, slightly warm, but, MUCH cooler than it did when it went crazy) I key it up and adjust the power setting to about 1 watt (I know the on-board meter is not that accurate, but, close enough for minor setup)and it seems to work just fine. Plenty of audio and as I said before, everyone says it is loud. But, thankfully, not annoying as some imports tend to be. SWR on the antenna I'm using (102" whip with spring, behind cab of truck, about 3 1/2 feet from cab and 3-4 feet from front of trailer............sloping belly dump trailer) SWR is 1:6:1 on 40 and about the same on channel 1. Around channel 20 it is about 1:3 or so.
Hope this critter keeps working, so far, other than not being able to use the Talk back, it works just fine.
trucker

 

[Robb]

Thanks! I have been keeping a close watch for heating on the case. So far,
it has run cool to the touch. (well, slightly warm, but, MUCH cooler than it did when it went crazy) I key it up and adjust the power setting to about 1 watt (I know the on-board meter is not that accurate, but, close enough for minor setup)and it seems to work just fine. Plenty of audio and as I said before, everyone says it is loud. But, thankfully, not annoying as some imports tend to be. SWR on the antenna I'm using (102" whip with spring, behind cab of truck, about 3 1/2 feet from cab and 3-4 feet from front of trailer............sloping belly dump trailer) SWR is 1:6:1 on 40 and about the same on channel 1. Around channel 20 it is about 1:3 or so.
Hope this critter keeps working, so far, other than not being able to use the Talk back, it works just fine.
trucker

Does it have a heat sink on the back of it? If no; then put one on. They are cheap and may stave off a future failure. It's a need; not a want. If it's got a dinky heat sink, then get something beefier if you want some more insurance.

Hmmm . . . The SWR reading over such a short bandwidth indicates that something is not right with that antenna - or more likely - its installation. That 108" whip/spring antenna is capable of being nearly 2mhz wide with a low and flat SWR. In other words - it should be going from ~26.5mhz to ~28.5mhz with a flat SWR. It isn't. Yours isn't even flat OR low across a mere 40 channels (much less than 1mhz width).

Have pictures of that antenna - installed?
That could help a lot . . .

 

[trucker]

Does it have a heat sink on the back of it? If no; then put one on. They are cheap and may stave off a future failure. It's a need; not a want. If it's got a dinky heat sink, then get something beefier if you want some more insurance.

Hmmm . . . The SWR reading over such a short bandwidth indicates that something is not right with that antenna - or more likely - its installation. That 108" whip/spring antenna is capable of being nearly 2mhz wide with a low and flat SWR. In other words - it should be going from ~26.5mhz to ~28.5mhz with a flat SWR. It isn't. Yours isn't even flat OR low across a mere 40 channels (much less than 1mhz width).

Have pictures of that antenna - installed?
That could help a lot . . .

Sorry I did not see your post before now.
The heatsink on the back is not as heavy as the one on my Connex 3300HP.
I am looking for one similar to what I have seen on some of the Stryker radios. Those things are huge compared to the one on the 3400HP. 1/4 inch thick on the back plate and the fins are much thicker too. Have yet to notice any heating problems since the repair work was done.
As for the SWR, I agree, it should be lower. But, given where the antenna is located, between the back of the cab of my truck (2007 Kenworth daycab) and the front of the sloping front of the belly dump trailer I pull, I am certain that has a big effect on the SWR. I have the antenna mounted on a bracket between two catwalks behind the cab. It is about 3' from the back of the cab (composite material over a metal framework) and 3 1/2' from the front of the metal trailer. I am planning to build an "A" shaped bracket to mount the antenna higher up and hope that will help too. I'm sure that I also need to add more ground straps to the frame even as it is right now.
trucker

 

[psycho]

Hi, a good friend of mine just gave me his Connex 3400 HP today. He has had it less than three months. And in that time, it has blown the finals twice!!
The first time he took it back to the shop where he got it. (after about a week)
And paid to have the finals replaced. Repairman said his antenna or coax was bad. He bought a new antenna and coax. Seemed to work just fine for a little over a month. Then, one day it blew the finals again! Took it to a different shop and the tech there said yep, the finals are toast. Installed new ones and it seemed to be working fine. Today, it blew the fuses (10amp) twice. And the radio was HOT (almost to the point of being untouchable) by the power connector. The second time he replaced the fuse, the radio stayed working, but, again, it was HOT near the power connector. He was so mad at the radio
that he pulled it out this evening (we drive rock trucks at the same company)
and handed it to me. I offered to buy it, but no dice. Give away he said. He said he was reinstalling his old Cobra 25, which has never had a problem.
(he even used it when he put it in the shop the first time and never a problem)
I guess what I need to find is a good schematic of the radio(if it exists).
i have done a Google search and come up empty handed for a schematic , much less, any good info on known problems with this radio.
Any suggestions (such as known voltages at test points.....haven't opened the radio up yet) would be appreciated.
Trucker

Send it out for repair to someone who knows what he is doing.

 

[trucker]

Send it out for repair to someone who knows what he is doing.

I believe that I mentioned on the previous page that is what I ended up doing. And the radio works fine. (talk back is crappy, but, otherwise, it is a good radio)
trucker

 

[treyzguy]

Connex..other problem

JUST LIKE ANY MANY OTHER DRIVERS, i BOUGHT THIS CONNEX-3400 HP FROM A DRIVER WHO WAS LOW ON CASH:sneaky2: ANYWAYS, IT WAS HOOKED UP AND WAS WORKING. I BOUGHT IT FOR $100 AND WAS HAPPY TO PUT IT IN MY TRUCK. WELL...I SOON NOTICED THAT IT WOULD BE RECVNG AND TRANSMITTING, THEN ALL OF A SUDDEN THE SWR METER WOULD JUST DROP. NOTHING. I'D HAVE TO RAP IT TO GET IT TO FUNCTION AGAIN..IT KEPT DOING THIS.
I STOPPED AT THE TA IN GREENCASTLE, PA TO LET THE LOCAL CB GURU CHECK IT OUT. HE TWISTED IT, PROBED IT, DONE SOME SOLDERING AND TWEAKING THEN CHARGED ME $30. IT WAS FINE FOR 3 WEEKS, NOW ITS DOING IT AGAIN. HE SAID THAT WHOEVER HAD WORKED ON IT LAST HAD LEFT SOLDER TITS ON THE BOARD THAT WAS BRUSHING THE CHASSIS AND CAUSING SHORTS. IT DOESNT GET HOT, IT DOESNT MAKE THE OLD ELECTRONIC MELTING SMELL. IT'S DEFINITELY PEAKED AND TUNED AND KICKS OUT ENOUGH POWER FOR ME. I KEEP IT ABOUT 40% OUTPUT.
HOWEVER, EVEN THOUGH THIS MODEL COMES WITH A TALK BACK INSTALLED, SOMEONE ADDED ANOTHER ONE. MOSTLY I NOTICE IF THE RADIO IS IDLE AND I'VE NOT USED IT FOR A BIT(BUT POWERED UP) THATS WHEN IT HAPPENS. NOW, WHADDAYA THINK?:headbang

 

[Watergate]

JUST LIKE ANY MANY OTHER DRIVERS, i BOUGHT THIS CONNEX-3400 HP FROM A DRIVER WHO WAS LOW ON CASH:sneaky2: ANYWAYS, IT WAS HOOKED UP AND WAS WORKING. I BOUGHT IT FOR $100 AND WAS HAPPY TO PUT IT IN MY TRUCK. WELL...I SOON NOTICED THAT IT WOULD BE RECVNG AND TRANSMITTING, THEN ALL OF A SUDDEN THE SWR METER WOULD JUST DROP. NOTHING. I'D HAVE TO RAP IT TO GET IT TO FUNCTION AGAIN..IT KEPT DOING THIS.
I STOPPED AT THE TA IN GREENCASTLE, PA TO LET THE LOCAL CB GURU CHECK IT OUT. HE TWISTED IT, PROBED IT, DONE SOME SOLDERING AND TWEAKING THEN CHARGED ME $30. IT WAS FINE FOR 3 WEEKS, NOW ITS DOING IT AGAIN. HE SAID THAT WHOEVER HAD WORKED ON IT LAST HAD LEFT SOLDER TITS ON THE BOARD THAT WAS BRUSHING THE CHASSIS AND CAUSING SHORTS. IT DOESNT GET HOT, IT DOESNT MAKE THE OLD ELECTRONIC MELTING SMELL. IT'S DEFINITELY PEAKED AND TUNED AND KICKS OUT ENOUGH POWER FOR ME. I KEEP IT ABOUT 40% OUTPUT.
HOWEVER, EVEN THOUGH THIS MODEL COMES WITH A TALK BACK INSTALLED, SOMEONE ADDED ANOTHER ONE. MOSTLY I NOTICE IF THE RADIO IS IDLE AND I'VE NOT USED IT FOR A BIT(BUT POWERED UP) THATS WHEN IT HAPPENS. NOW, WHADDAYA THINK?:headbang

Carlisle PA is just up I-81 from Greencastle, and is home to DTB Radio. DTB is a member here on this forum and comes HIGHLY recommended by the forum members. I would suggest you contact him for repair. www.dtbradio.com.

Solder tits.
Radioactive Radios.

Sent from my DROIDX using Tapatalk 2

 

[9C1Driver]

Heck if it's a radiohacktive radio that's the problem right there. I wouldn't let that place touch my toaster much less an expensive radio.

 

[Watergate]

Don't know if it's a radiohacktive job or not. I just saw him use the term "solder tits" and a few places came to mind.

Sent from my DROIDX using Tapatalk 2

 

[SGTSmokdu]

Final update, the 3400HP is alive and working well. FINALLY !!
How long it will last, is anyone's guess. The bad voltage regulator
nailed several other parts, including one of the finals, (had both replaced
as I feel it's better to have a fresh, matched set) and the trimmer, and three
other capacitors in the BIAS adjustment section for each final. Now, the BIAS
voltage stays steady at 3.2 volts on each final. The only complaint I have is the
talkback is super sensitive. With my Connex 3300HP, I can have it on and hear
myself clearly without any squealing feedback. With the 3400HP, just turning it
on and with the mic gain about half way, it squeals. Turn the mic gain below that
and it goes away. And I cannot hear anything on the talkback. Don't really need it
but, it is kind of nice in a way. Otherwise, everyone that has heard the radio says
it has plenty of punch in the audio and is LOUD. (using an Astatic 636L)
Just hope it lasts a while. I'm keeping my 3300HP as a backup. Several of the guys
at work want it. ................Not happening!!


From a Galaxy far far away...

 

[577-Jersey]

Thats a 3600-15c board alot like the 14b but traces are slightly different..you can use the galaxy 33 procedure for it...the regulator on them is a 817 it needs to be upgraded to a TIP 36c or it wont last long..set the bias voltage off the gate to 3.75v driver and 3.50v final,,then set dead key for low side 2 watts high side 7 watts,,and drop the hammer,,good luck!!

577-Jersey

 

[Cpt shakes]

Is there anywhere I can find the alignment procedures for a connex saturn cx-33 s s b? I understand that it is a connex 3400 hp board. However, I have been unable to find the alignment procedures. Can anyone help please?

 

[Heath Streich]

Sorry to post in an old thread, new here, I'll get to the point. I bought a used 3400hp from a cb shop. Went back 3 times because I was told by others it sounds like crap (over modulated) opened it and found some kind of mod done, can't seem to find anything online like a schematic, would be eternally grateful for some good pictures of the inside so I can put it back to factory