Intek tornado 34s cb radio follow on from lcl2740

[Alucard]

As far as I can see the channels from 1-23 are spot on, jumping the alpha channels in the correct place. The channels around 24 are jumbled up from when U.S. rigs only had 23 channels and the rest were allocated later.
However 24 should drop 2 channels below 23 and yours only drops one and the channels seem messed up there onwards. As Digger said pin 10 should go high near the top of the band but that still doesn't fix it. I can't see any pattern to suggest pins shorted or open.
Over to you Ibcomms ...

[lbcomms]

Is there a pin at switch positive only from channels 26 upwards? If there is, the switch could be from a 3 band radio that used binary adder chips instead of crystals for each block of 40 channels. If that's the case, you'll need to add the missing parts (either an EPROM, microcontroller, or a pair of 4 bit binary adders such as 4008 or 7483 chips) to address a "+390 KHz" shift. This will reinstate the wrong channels.

If there is not a pin on the switch that goes positive from channels 26 upwards, then you'll need to replace the switch, either with the correct type or by making something from scratch like an Arduino with a rotary encoder to drive the PLL and LED with however many channels you desire.

The one thing that doesn't make sense is the 1/2 error on channels 24 and 25 - I ignored these as they could be a measurement error.

[mastercare]

So from what I can tell that you have told me, the channels 26 to 24 should look like this(Had a ago at rebuilding the tables from what I understood)?

Code: Select all

-------GOOD-------------------------(untested)
CH26 - 0 0010 1011   0.43   0.430MHZ
CH27 - 0 0010 1100   0.44   0.440MHZ
CH28 - 0 0010 1101   0.45   0.450MHZ
CH29 - 0 0010 1110   0.46   0.460MHZ
CH30 - 0 0010 1111   0.47   0.470MHZ
CH31 - 0 0011 0000   0.48   0.480MHZ
CH32 - 0 0011 0001   0.49   0.490MHZ
CH33 - 0 0011 0010   0.5    0.500MHZ
CH34 - 0 0011 0011   0.51   0.510MHZ

Did a improv with a bread board but had no results despite the pins reading right but that may be my lack of understanding of this rig's i/o
Thanks, paul

[mastercare]

hi well wired up bread board with known configuration as in ch1 and the radio works 26.965 my son thanks to ibcomms help managed to complete the table above faulty chs...but this did not work....so got recheck these....of course this rules out using the ch switch altogether...
so if the ch sw is faulty i need to replace it....as i think ibcomms is right all along...its strange as to why its happened...getting the right one is now my problem..
thanks all
paul

[lbcomms]

That table was generated automatically (using Excel) using the data you supplied and formulas to do the rest.

If there is not a pin on the switch that goes positive from channels 26 upwards then you'll have to replace the switch. Getting the right one may be nigh on impossible, so you'll probably have to adapt something else in there. First step is to find something that physically fits, second it to use a middleman circuit (EPROM, binary adders, or a microcontroller) to translate the 1's and 0's to suit the radio.

[mastercare]

hi ibcomms
ok ch 26 ill see if a pin goes high...ill let you know....had enough of it today...
cheers
paul

[Alucard]

If this rig was bought to me to fix I'd absolutely love it, it's a real head-scratcher. Sadly it's not so much fun trying to diagnose hands off, over the interwebs, in my head
So thanks to ibcomms for the frequency table. I think there's a few errors in the bit errors column but it doesn't make much difference to the diagnosis.
Claude posted a link to buy the proper channel change but if I were you I'd get one with 40 channels just so you can have a 40 channel readout, binary or bcd doesn't really matter if your using an Eprom.
I'm still drawn to think there's some sort of modification done that is skewing the frequencies either from a switch or rewiring of address lines to the PLL.

But then I'm not a rig doctor.

Just a lonely crustacean looking for love

[mastercare]

Hi all well I've ordered from the company Claude sent me....so a new switch I hope is on the way...
this will at least rule one thing out...
all we can do now is wait...
it looks like alot pins to unsolder....wish me luck.. just checked 30 pins ouch
thanks all
paul

[Alucard]

Hope it works out.
Claude continues to impress me with his wealth of info, he should compile a database or something of it all, I'd happily pay a few quid for it

[mastercare]

Hi Alucard
guess what im going to wrap up and post this rig to you to sort out...
if the switch does not cure it....guess that be ok?

paul

[14CS06]

Hello

https://malzev.tripod.com/cb-funk/ept3600.htm

https://malzev.tripod.com/cb-funk/cbs2100b.htm

http://www.cbtricks.com/radios/galaxy/d ... el_pcb.htm



http://www.cbtricks.com/radios/galaxy/d ... 2z_sch.gif




viewtopic.php?style=7&f=53&t=55598

@+
Claude

[Alucard]

Hi Alucard
guess what im going to wrap up and post this rig to you to sort out...
if the switch does not cure it....guess that be ok?

paul

I hope it's not too late for you to cancel the order, I've just found out the channels on your radio are correct yes CORRECT!
I don't know the reason for it yet, I've been translating Italian CB sites and as you can imagine it takes a while.

This is a paste from one site but there are others that verify it..

channels.jpg

Gotta go, be back this evening.
Al.

[14CS06]

Hi Alucard
guess what im going to wrap up and post this rig to you to sort out...
if the switch does not cure it....guess that be ok?

paul

I hope it's not too late for you to cancel the order, I've just found out the channels on your radio are correct yes CORRECT!
I don't know the reason for it yet, I've been translating Italian CB sites and as you can imagine it takes a while.

This is a paste from one site but there are others that verify it..

channels.jpg

Gotta go, be back this evening.
Al.

Hello

From https://www.rogerk.net/forum/index.php?topic=30472.0

https://www.rogerk.net/forum/index.php?topic=71974.0

http://www.rogerk.net/forum/index.php?topic=33917.0

http://www.radio-amatori.it/forum/viewt ... 4&start=30

@+
Claude

[mastercare]

Hi what can i say.....this rig is has doing my head in....i was just about to rip out the ch selector...alucard ...you just caught me in time...
regards cancelling sw i see if its been dispatched..what a nightmare enough to put me on drugs...lol
thanks claude alucard ...ill update more when i know
paul

[mastercare]

hi all
so we are right back to square 1 it seems so up to ch26 is fine after that it goes down...but if we now convert to 10 metres will that matter..
as long as i write down the new freq 1>26 then 26>34...ok it will be weird but is this still a goo go or what happens next..
ideas please...
thanks all for your patience on this long story......

paul