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I have a DX 44V EPI360014B board. After warm-up I can change channels, which is reflexed in the channel display, but the actual channel stays where it was at...anyone had a similiar problem or a fix?

Check the voltage while change channel at Pins 10 to 17 on the PLL chip (IC5) you should see the voltage change from 0 to 8 volts depending on which channel you are on. If the voltage does not change then check the voltage while change channel at Pins 1, 3, 5, and 7 of (IC1) you should see the voltage change from 0 to 8 volts depending on which channel you are on. Let us know how you get on.

Rick wrote:Check the voltage while change channel at Pins 10 to 17 on the PLL chip (IC5) you should see the voltage change from 0 to 8 volts depending on which channel you are on. If the voltage does not change then check the voltage while change channel at Pins 1, 3, 5, and 7 of (IC1) you should see the voltage change from 0 to 8 volts depending on which channel you are on. Let us know how you get on.

Rick,

I did get voltage changes on pins 10 -17 on IC5...(i) went no further. There was a negative shift on some pins.

Check the voltage at TP2 on channel 1 and channel 40 on the CB band this is band (D) or (E), let us know what voltage you have?

Is the RX/TX LED changing colour when you key-up?
Red in TX and Green in RX.

What channel is the radio stuck on?

Has any one been in the radio and been playing with any of the pot and coils trying to tune it-up?

Rick wrote:Check the voltage at TP2 on channel 1 and channel 40 on the CB band this is band (D) or (E), let us know what voltage you have?

Is the RX/TX LED changing colour when you key-up?
Red in TX and Green in RX.

What channel is the radio stuck on?

Has any one been in the radio and been playing with any of the pot and coils trying to tune it-up?

Rick,

Voltage at TP2 on Ch. 1 is -3.3 on 40 at -2.7
Yes, LED RX/TX working
Sticks on Ch. 19
Back top and bottom cover screws missing so my answer is yes with played around with. No obvious screwdriver track's

It maybe a bad PLL chip, but before you go down that road. Let check some thinks out, the PLL works in binary you do not need to understand this all you need to do is give me voltages at Pins 10 to 17, and if you can write them like so

Pin 10 = 0v
Pin 11 = 8V
And so on

If you can do 4 channels for me. Channel 1,2,3,19 I should be able to work it out from them.

Also check the voltages on Pin1 to 9 on the PLL.

Rick wrote:It maybe a bad PLL chip, but before you go down that road. Let check some thinks out, the PLL works in binary you do not need to understand this all you need to do is give me voltages at Pins 10 to 17, and if you can write them like so

Pin 10 = 0v
Pin 11 = 8V
And so on

If you can do 4 channels for me. Channel 1,2,3,19 I should be able to work it out from them.

Also check the voltages on Pin1 to 9 on the PLL.

Here you go....

Ch. 1 Ch. 2 Ch. 3 Ch. 19

Pin 10 4.5v Pin 10 4.3v Pin 10 4.2v Pin 10 4.0v
Pin 11 2.9v Pin 11 2.9v Pin 11 2.9v Pin 11 2.9v
Pin 12 4.4v Pin 12 4.2v Pin 12 4.1v Pin 12 2.8v
Pin 13 2.9v Pin 13 2.9v Pin 13 2.9v Pin 13 2.8v
Pin 14 2.9v Pin 14 2.9v Pin 14 2.9v Pin 14 4.1v
Pin 15 4.3v Pin 15 2.9v Pin 15 2.8v Pin 15 4.1v
Pin 16 3.0v Pin 16 4.2v Pin 16 4.1v Pin 16 4.1v
Pin 17 2.9v Pin 17 4.2v Pin 17 2.9v Pin 17 2.7v

Pin 1 2.7v
Pin 2 -.5v
Pin 3 -.3v
Pin 4 -.3v
Pin 5 -.7v
Pin 6 2.7v
Pin 7 -2.4v
Pin 8 2.7v
Pin 9 -3.8v

I only used Ch. 19 for Pin 1 - 9. Didn't know if you wanted 1,2,3,19

I do not think you are doing the voltage check correctly.

You test meter needs to be set to DC, connect the Black probe to ground one of the tuning cans is ok or better still is to the Black negative lead at the power socket or your power supply, and use the Red probe to do the voltages test.

You will know if you have it right by putting Red probe to the positive lead at the power socket or your power supply it should be about 13 to 13.8 volts, if it is correct carry on and do the test again.

You do not need to use my quote in you post, and please do not use Red text only Black.

Your right........I was using a chassis ground. Using a can the voltage reads higher, I will retake the readings. Power supply is 13.8v

Here are the updated values...sorry for the mess-up, I learned that not all grounds are equal.



Ch. 1 --------- Ch. 2 --------- Ch. 3 ---------- Ch. 19

Pin 10 = 0v --Pin 10 = 0v -- Pin 10 = 0v -- Pin 10 = 0v
Pin 11 = 7.8v Pin 11 = 7.7v Pin 11 = 7.7v Pin 11 = 7.6v
Pin 12 = 0v -- Pin 12 = 0v --Pin 12 = 0v -- Pin 12 = 7.7v
Pin 13 = 7.8v Pin 13 = 7.8v Pin 13 = 7.7v Pin 13 = 7.7v
Pin 14 = 7.8v Pin 14 = 7.7v Pin 14 = 7.8v Pin 14 = 0v
Pin 15 = 0v -- Pin 15 = 7.7v Pin 15 = 7.8v Pin 15 = 0v
Pin 16 = 7.8v Pin 16 = 0v -- Pin 16 = 0v --Pin 16 = 0v
Pin 17 = 7.8v Pin 17 = 0v -- Pin 17 = 7.7v Pin 17 = 7.7v

Pin 1 = 8v
Pin 2 = 3.8v
Pin 3 = 4.1v
Pin 4 = 4.1v
Pin 5 = 3.6v
Pin 6 = 7.9v
Pin 7 = 1.5v
Pin 8 = 7.9v
Pin 9 = .1v

It looks like you have 2 faults, first is the PLL chip IC5 has failed and the 2 binary adder chips IC1 and IC2. That is assuming you have checked the right Pins.

What you should have for Channel 1
Channel 1
Pin 17 = 1
Pin 16 = 1
Pin 15 = 0
Pin 14 = 1
Pin 13 = 1
Pin 12 = 0
Pin 11 = 1
Pin 10 = 0

1 which means (HI) the pin has volts between 7 and 8 volts
0 which means (LOW) the pin has no volts (Zero).

Channel 2
Pin 17 = 0
Pin 16 = 0
Pin 15 = 1
Pin 14 = 1
Pin 13 = 1
Pin 12 = 0
Pin 11 = 1
Pin 10 = 0

It would be a good idea to check the code coming from the Channel switch, this is the wires coming from plug J304 White, Violet, Blue, Green, Yellow, Orange, Red, Brown, and Black, if you do check them, do it as before Channel 1, 2, 3, and 19.

Not good news.......I used the pin out information for MC145106P, so I believe I got that right. Thanks, for sticking with me on this, you have been a great help. I will check the wiring tomorrow, got to go to work.

Before you change any chips, can you let me have the VCO voltages again, that is TP2 on channel 1 and 40 also channel 1 on the Low band (A) and 40 on Hi band (G).

Do all the testes below on the CB band which is band (D) or (E) Channel 1, 2, 3 and 19.

You could also check the codes at plug J1 on the Band PCB (EPT004410Z) the Black wire Pin (1) is 8 volts and Brown Pin (2) is Ground, you do not need to test the Red wire Pin (3) as this is the 10KHz switch wire.

I located the code's....what procedure would I use to evaluate as they are numeric?

EDITED: I think I now understand what you are asking, as the code is binary, an depending on a returned voltage it would indicated a (0) or (1). So if I am on the right tract all you would need are the voltages from J1? If I understand your instructions I would use pin 2(ground) and all remaining wires except pin 3(10kHz).

If this is correct what format would you want them in:

White = (?)v
Violet = (?)v
an so on for all wires, for each channel 1,2,3,19

The Codes are Binary, which are (1), and (0).
1 is known as HI (+ Volts)
0 is known as LOW (Zero volts)

You can write the code like so
Pin 17 = 1
Pin 16 = 1
Pin 15 = 1
Pin 14 = 1
Pin 13 = 0
Pin 12 = 0
Pin 11 = 0
Pin 10 = 0
The codes above are for CH1 on Band (E) at the PLL chip.

I do not use wire colours, I just do the test in a logical way, I am not trying to be big headed it just experience. But if you need to use wire colours do so I can work it out, it just makes it harder.

The Codes coming out of the Band Board on plug (J1) same as above.
The codes for Channel (1, 2, and 3) on Band (E) are like so at Plug J1
CH1 = 1,1,1,1,0,0,0,0
CH2 = 0,0,0,0,1,0,0,0
CH3 = 1,0,0,0,1,0,0,0

The Channel Selector codes are the same codes on each band at plug (J2) on the Band Board (EPT004410Z) or (EPT004410A).
You need to check the codes at Plug (J2) just in case you have a bad Channel Selector.
The codes for Channel (1, 2, and 3) are like so at Plug J2
CH1 = 1,1,0,1,1,0,1,0
CH2 = 0,0,1,1,1,0,1,0
CH3 = 1,0,1,1,1,0,1,0
I do know now which colour wires are which this is for you to work out.
I think the Yellow wire is 8 Volts so you do not need to check this one.

When it comes to doing the Plugs like (J1 and J2), you need trace the track on the board to the chips.
Like IC1 and IC2 the output pins are 10, 11, 12, and 13 they go to plug (J1). It is not easy to explain so maybe it is just as eases to just change the to chips on the Band Board, that if you have the (EPT004410Z) if it is the later Band Board (EPT004410A) in this case you will need a new board as the chips are SMT and are not easy to change.

You could just change the chips and hope for the best, as this maybe the easy way out.

Rick,

Finally found time to continue. Here are the code(s) for Band (E) PLL chip

Channel 1
Pin 17 = 1
Pin 16 = 1
Pin 15 = 0
Pin 14 = 1
Pin 13 = 1
Pin 12 = 0
Pin 11 = 1
Pin 10 = 0

Channel 2
Pin 17 = 0
Pin 16 = 0
Pin 15 = 1
Pin 14 = 1
Pin 13 = 1
Pin 12 = 0
Pin 11 = 1
Pin 10 = 0

Channel 3
Pin 17 = 1
Pin 16 = 0
Pin 15 = 1
Pin 14 = 1
Pin 13 = 1
Pin 12 = 0
Pin 11 = 1
Pin 10 = 0

Channel 19
Pin 17 = 1
Pin 16 = 0
Pin 15 = 0
Pin 14 = 0
Pin 13 = 1
Pin 12 = 1
Pin 11 = 1
Pin 10 = 0

Checking at J2 on Band Board (EPT004410Z)

CH 1 = 1,1,0,1,0,1,1,0
CH 2 = 0,1,1,1,0,0,1,0
CH 3 = 1,1,1,1,0,0,1,0
CH 19 = 1,1,0,1,1,0,0,0

So the code at the PLL looks ok. I do understand, explain again what the problem is.

Also can you give me the codes for channels 37, 38, 39, and 40 on band (E) at the PLL, and the voltage at TP2 on ch1 and 40 no each band, and voltages on the PLL Pins 1, 2, 3, 7, 8, and 9 on ch1 band (E).

Rick,

At times on Band (E) when changing channels the LED will indicate the desired change but the actual channel will not change.

Here is the requested data...on band (E) PLL chip.

Channel 37
Pin 17 = 0
Pin 16 = 0
Pin 15 = 0
Pin 14 = 1
Pin 13 = 1
Pin 12 = 1
Pin 11 = 0
Pin 10 = 0

Channel 38
Pin 17 = 1
Pin 16 = 0
Pin 15 = 0
Pin 14 = 1
Pin 13 = 1
Pin 12 = 1
Pin 11 = 0
Pin 10 = 0

Channel 39
Pin 17 = 0
Pin 16 = 1
Pin 15 = 0
Pin 14 = 1
Pin 13 = 1
Pin 12 = 1
Pin 11 = 0
Pin 10 = 0

Channel 40
Pin 17 = 1
Pin 16 = 1
Pin 15 = 0
Pin 14 = 1
Pin 13 = 1
Pin 12 = 1
Pin 11 = 0
Pin 10 = 0

And the following band voltage(s) at TP2

Channel 1
A(L) = 1.5v
B(L) = 2v
C(L) = 2.5v
D(L) = 3.1v
E(H) = 2.7v
F(H) = 3.2v
G(H) = 3.7v
H(H) = 4.4v

Channel 40
A(L) = 2v
B(L) = 2.5v
C(L) = 3.1v
D(H) = 3.8v
E(H) = 3.2v
F(H) = 3.7v
G(H) = 4.3
H(H) = 5.1v

Voltages on the PLL Pins 1, 2, 3, 7, 8, and 9 on Ch1 band (E)

Pin 9 = 7v
Pin 8 = 7.9v
Pin 7 = 2.7v
Pin 3 = 2.7v
Pin 2 = 3.7v
Pin 1 = 8v

have a Galaxy Jupiter with EPI360014B board with more or less the same problem...
channel display shows the channels going up or down, though output freqenty doesn't change 28.390 MHZ in A,B,C-band
29.215 MHZ in D,E,F-band
and I'm not realy technical enough to start repairing this..though..I'm learning..and reading all the topics here are veryyy educational..
Rick, I must say, read a lot over here and you are a genious! an electronic virtuoso!...I will put the transceiver aside for a while untill my knoledge is big enough and I dare making the steps for a repair, unless you tell me it's not worth it...

I would suggest trying to manually adjust the voltage for the VCO, by lifting one end of R116 (or cutting the track) which is between it and the PLL (pin 7) and then connecting up a Pot to provide a variable voltage to the VCO (between 0v and 8v) and see if turning the pot adjusts the frequency (like a VFO).

I have used this trick to diagnose PLL/VCO control problems, as it will tell you if the VCO is OK, also, while this is being done, you could monitor the voltage out of the PLL Phase Detector (pin 7) to see if it is shifting in voltage as it should depending upon the VCO frequency (from too high to too low), it would only output either its minimum voltage or its maximum voltage and will not float in between, the voltage will depend upon whether the VCO is outputting a lower or higher frequency then the PLL is trying to set it to.

If the PLL is reacting correctly (quite likely) you may find a bad smoothing capacitor (C101, C102) which is dragging down the PLL voltage, I have come across this type of fault on other types of radios.

This is a little technical but it may help others with a similar problem.

thanks a lot Scott! this is very fast reply, I will try this tomorow are the day after..
as my know how on electronics is basic..i will re-read this gently..and do this very slowly...but sure will keep you informed on the outcome.
thnks again!!
good night
michel

From a bit of a look at your last post, I noticed some voltages you mentioned on pins you do not need to be testing, all PLL inputs are on pins 17 though to pin 9 (17,16,15,14,13,12,11,10,9), pin 7 is the phase detector output (the output of the PLL which controls the VCO to give you your final operating frequency).

Also looking at the voltages you specify on TP2 on each band, the VCO appears to be working, along with the PLL control, which means that your radio SHOULD be producing different frequencies.

If you have a frequency counter you can test the downmix frequency (the frequency the PLL sees from the VCO, which tells it if it is on the right frequency or not).

If you connect a counter to the PLL at pin 2 you will see the downmix frequency, on Ch1 on band A it will be 0.910MHz (for a binary code of 91), on Ch40 it will be 1.350MHz (for a binary code of 135), if these are correct then the PLL and VCO are doing there jobs and the problem is elseware.

connex 3300 hp was doing samething replaced binary adder problem fixed

The Defpom wrote:From a bit of a look at your last post, I noticed some voltages you mentioned on pins you do not need to be testing, all PLL inputs are on pins 17 though to pin 9 (17,16,15,14,13,12,11,10,9), pin 7 is the phase detector output (the output of the PLL which controls the VCO to give you your final operating frequency).

Also looking at the voltages you specify on TP2 on each band, the VCO appears to be working, along with the PLL control, which means that your radio SHOULD be producing different frequencies.

It's been soom time since I have been able to get back to the DX44V. I was looking at the alignments page for Galaxy Export Radios. Checking voltage at TP2 following paragraph C. VCO ALIGNMENT(ref. para. 3 for setup) I found the following:
Channel 40 Band E/Hi - 27.405 Mhz.
TP2 - 3.17
Channel 1 Band A/Low - 25.165 Mhz.
TP2 - 1.46
Before adjusting L17 I wanted your input before I proceed.

Thanks,

jwPotts