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Canon5218
Junior Member
Username: Canon5218

Post Number: 20
Registered: 8-2006
Posted on Saturday, September 02, 2006 - 9:01 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey yall I got rid of the new Cobra 148GTL China made and got me a Galaxy DX-959. Brings up a couple questions.

Wondering if there is any channel mods besides the P6 and P5 mod. I talk up on LSB of 46 alot and that mod don't get me that freq. Does any of the other RCI 8719 mods work for this radio?

Next question, if I crank up AM High Power and SSB Power this will simply up my power and no alignment will be needed?
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2040
Registered: 9-2004
Posted on Saturday, September 02, 2006 - 10:19 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hey cannon,

the DX959 does not have the RCI8719 PLL in it.
it is the MC145106P.

you can get 27.465 by doing the P5 and P6 mod and then doing the 10khz mod.

i would not recommend turning up the AM power control, as it would only decrease your modulation, and make you sound quieter.
turn the AMC pot all the way up, and dont clip any parts in the mod. circuit.
turn the AM power DOWN to about 2.5 watts, and let the sucker swing up from there.
no one will notice the difference in your deadkey, but the modulation will be louder.

turn the SSB power up to about 15 watts, and no more.
you wont get out any further by turning it up more, but you will decrease the life of your final.

just so you know, with the radio set like this it will run a linear PERFECTLY!

good luck,
matt
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 3185
Registered: 7-2004


Posted on Sunday, September 03, 2006 - 12:01 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

some 949/959 & a few others used the ept6900 board, then the ept0696 board. they are virtually identical. even the rci8719 & mc145106p dip-version are EXTREMELY close in operation, as can be seen by SEVERAL frequency-changing mods. the 145106 was supposed to throw the fcc off the trail by it being either non-modifiable, or at least not modifiable to the 10 meter band without an xtal change. look at the direction of the pin-outs & which ones are used for which mod & you'll see the similarities. for all intents & purposes, MOST 8719 mods work on the 959, just confirm what chip is in it, (145106 in newer ones), & mod that IC accordingly.

kid is correct on how to obtain 27.465....no matter what chip it contains. and yes, getting carried away with 'audio' in these versions can easily make it sound POOEY-like
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Canon5218
Junior Member
Username: Canon5218

Post Number: 22
Registered: 8-2006
Posted on Sunday, September 03, 2006 - 8:16 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sounds good guys. I really appreciate the responses. I was just going by all of the online info I have seen on the DX959 and everything said it had the RCI8719 PLL.

Guessing the P5 and P6 works on either chip version?
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Canon5218
Junior Member
Username: Canon5218

Post Number: 23
Registered: 8-2006
Posted on Sunday, September 03, 2006 - 9:46 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

One more question. Can I do the 10kHz Slide AND unlock the fine tune control?
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 3186
Registered: 7-2004


Posted on Sunday, September 03, 2006 - 7:35 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

just open it up to check....but the newer 1 should be a 145106. use the mods for the CHIP that you have...
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Hotwire
Senior Member
Username: Hotwire

Post Number: 1721
Registered: 1-2005


Posted on Sunday, September 03, 2006 - 7:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Canon, I picked up a really used totally stock 959 awhile back for real cheap. I bought it to actually do mods on it, you know, to learn. Great radio no doubt.
I did the clarifier mod method 2 with success. Its not hard but you do need to take your time and be careful what you do. I think I had to take apart the front of the radio to get to the parts of the board I needed. After you do the clarifier mod you should have it alighned.
As for the 10 kc mod? Man it looked a bit more complicated! It involved cutting a trace and at the time I was not sure of my skill. Only advice I can give if you decide to try it is double check everything and take your time. One wrong move and you could have a situation on your hands! good luck
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Canon5218
Junior Member
Username: Canon5218

Post Number: 24
Registered: 8-2006
Posted on Sunday, September 03, 2006 - 8:31 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Opening her up here in a little bit Pat. I will let you know my findings.

Hotwire: DId you see the 10 kc mod where you simply add a 300 pF in series with the 10.240 reference crystal?

Hotwire: The clarifier mod you done...was it this one?
Unlock the Fine Tune Control!
#1 ~ Remove R-113
#2 ~ Remove D68
#3 ~ Remove D-38
#4 ~ Place wire across D-38 mounting holes.
#5 ~ Place wire from J-14 pin +8V to J-9 pin F1
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Canon5218
Junior Member
Username: Canon5218

Post Number: 29
Registered: 8-2006
Posted on Monday, September 04, 2006 - 10:37 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hotwire: Did you find that an alignment was needed after the mod? Did you use the built in freq counter to align or a 6 digit external?
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Hotwire
Senior Member
Username: Hotwire

Post Number: 1732
Registered: 1-2005


Posted on Monday, September 04, 2006 - 11:09 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

You will need an external counter 6 digit counter. I had my trusty tech align it for me. It needed an alignment even before I did the mod so I'm not sure exactly how much it would go out of alignment after a mod.
I really bought the radio just for the purpose of learning. It was not up to par compared to the qaulity of the SSB radio I'm used to. On AM it got great reports and was loud and clear.
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 3191
Registered: 7-2004


Posted on Monday, September 04, 2006 - 4:35 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

8719-99??? my shack is in a shambles due to construction on my house, so from memory.....pin 10 & pin 11 ARE P5 & P6 on an mb 8719 & rci8719. i BELIEVE they are different PINS on an mc145106m, which is why they tell you to take 'em off the channel slector-less confusion. where they are on an rci8719-99, i don't know??? or is that a relabled mc145106??? you should be able to take 'em off the channel selector as they are marked, you then need to see which freqs you get-the ones from an mb8719 or the ones from an mc145106. i would then do the standard clarifier mod & the 10 kc switch as on cb tricks-for better frequency stability. i never tried the 'other' clarifier mod for a 145106, nor do i remember where the differences are, so i can't even guess which works-the mb8719 mod, or the 1 on cb tricks.

take your time & do CLEAN mods/cuts. you can return them to stock & try the 'other' mods if need be.

adding and/or removing parts from the synthesizer circuitry can cause a realignemnt to be required afterwards. if you have consistant (friend) distant signal, & no DX noise, you can align it real close by ear....more or less.
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Canon5218
Junior Member
Username: Canon5218

Post Number: 30
Registered: 8-2006
Posted on Monday, September 04, 2006 - 7:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Done the P5 & P6 Switch mod today and I got the same exact list of freq's thats listed in the chart on CB Tricks. I beleve they have the PLL listed as a 8719 on there also.

Done a very clean install of the switches and wiring...hey its what I do for a living. =) hehe

I may meter out P5 and P6 to the 8719 and see what pins they are later. I will let you know my findings.

Yes RANGER RCI8719-99 is what the chip reads.
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2047
Registered: 9-2004
Posted on Monday, September 04, 2006 - 11:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

good deal canon!

glad to know its working out.
matt
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Canon5218
Junior Member
Username: Canon5218

Post Number: 32
Registered: 8-2006
Posted on Tuesday, September 05, 2006 - 12:01 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yeah Matt it's working out real good on the freq expansion.

Next up...clarifier unlock and the 10kHz mod! Wish me luck!

For the 10kHz mod I will be using the mod on CB Tricks which seems easy enough...SPDT is bout it.

For the clarifier mod I am still in limbo.

The mod Lon has listed it this:
#1 ~ Remove R-113
#2 ~ Remove D68
#3 ~ Remove D-38
#4 ~ Place wire across D-38 mounting holes.
#5 ~ Place wire from J-14 pin +8V to J-9 pin F1

The mod CB Tricks has is this:
1. First, remove power to the radio. Remove the bottom chassis cover of the radio.
2. Remove R113 and D68 as shown above.
3. Connect a jumper wire between +8V and J9 pin F1.
4. Perform an PLL alignment as shown below.


CB Tricks does not show the need to remove D38. Anyone have any insight here? What will I gain from removing D38?

Also CB Tricks has this version listed:
. First, remove power to the radio. Remove the bottom chassis cover of the radio.
2. Remove JP195 and JP196.
3. Connect a jumper wire between +8V and J9 pin F1.
4. Perform an PLL alignment as shown below.


What the difference in there two versions of the mod?
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2049
Registered: 9-2004
Posted on Tuesday, September 05, 2006 - 10:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

here's a whole bunch of mods for the DX959:
these are from the defpom site:
(all ECG numbers correspond to NTE numbers. IE: ECG583=NTE583)
Modulation Limiter:

Q39 is the modulation limiter for the EPT06960Z board. For the Galaxy DX949, you may remove the limiter. For the Galaxy DX959, I recommend placing a 1K resistor in series with the emitter leg of Q39. Removing the limiter on the SSB model causes severe "garbling" while in the SSB mode. Ample performance may be achieved by simply turning up VR16 and wiring a good aftermarket power microphone for use with the radio. I am using the Astatic D104M6B microphone and I can not run the microphone and radio fully open without massive audio distortion. This radio has plenty of audio to spare.

AGC (Automatic Gain Control) Improvement

Like the EPT690010Z, the automatic Gain Control response is controlled via resistor R42 (100K). If you find that your local buddies sound "garbled" on SSB, you can remedy this by changing R42 to anywhere between a 33K to a 56K resistor. All radios seem to respond differently depending on the value used. You may have to experiment with different values within this range. Like the EPT690010Z, you can make the AGC variable by installing a 100K potentiometer.

Power Amp Improvement (2SB754) - Q54

This is the best improvement you can make to this chassis. The stock device is a 2SB754, which is a 60-watt, 7A power amp device. This does fine for stock radios. However, in order to stabilize the voltage on the board after improving the RF output and boosting the modulation, the 2SB817 becomes the better choice. The 2SB817 is a 100-watt, 12A device which allows greater voltage stability for the entire radio as a whole. I ran my test DX959 with the stock device and noticed quite a bit of wobble and light dimming. After replacement, the radio responded with almost no blinking, zero wobble and a healthy increase in RF output as well as swing. Replacing this device also allows you to increase the input voltage to 14.5VDC, provided you also replace all the 10V caps in this section of the board to 16V ones.

AM AF Amplifier Improvement - Q55

This is another improvement, which has previously been published for the EPT690010Z. The stock AF Amplifier is the 2SA473. Replacing this with the 2SA1012-0 or the ECG153 will improve the clarity and volume of the modulation. It will also run much cooler which provides stability for the device. If you plan to use the DX959 or DX949 with the provided stock microphone, this upgrade is highly suggested for maximum AM modulation.

Receive Improvement - D30 & D31

The stock AM Detection diodes are 1N60P devices. These are adequate but can be greatly improved by replacing them with the ECG583 Schottky devices. The replacement diodes allow greater copy of distant stations without allowing your local buddies to overdrive your radio. I have obtained a gain increase of approximately 3db on stations more than 20 Miles away. This modification is especially noticeable in mobile installations where you are forced to use an inferior antenna system (as compared to a base station setup).

Noise Blanker Improvement - D1 & D2

The Noise Blanker diodes can also be replaced with the ECG583 Schottky devices. The improvement over the stock diodes can be rather dramatic, depending on how noisy the environment is around the operating location. Again, this modification is most noticeable in radios being used in mobile installations.


RF Output Increase Modification

This modification will allow the DX959 & DX949 to exhibit the RF output and swing of the Galaxy DX-series 10-meter radios. The board was always capable of this type of output; it was simply choked off by the design engineers in order to meet FCC 11-meter specifications.

The first thing you need to do is turn up VR14 which is the AM high power variable. If you?ve already done the modulation improvements, you should be able to dead key about 8-10 watts and swing around 15 watts. 18 watts is probably the best you?ll get (using a peak-reading Bird wattmeter). Now, perform the following modifications:

1. Remove C218 (3pf) and discard.
2. Change C216 (470pf) to a 1000pf (100V mylar-type)
3. Remove C210 (470pf) and discard.
4. Remove C199 (560pf) and reinstall it in the C210 spot.

Adjust your dead key to around 5 watts. I was able to achieve average peak swing readings of around 35 watts. Depending on the audio input (voice or whistle), I was able to whistle myself to readings of over 40 watts peak! There was a slight decrease in modulation and it seemed as though I was really pushing it. I found that I was able to regain the modulation level by lowering the dead key (using the RF Power control on the radio face) to around 2.5 watts. This netted peak swing readings of just around 28 watts! More than enough given the fact that the modulation was over 95% and crystal clear! this new radio has "the stuff." You just have to work slightly harder to get at it.



Known Factory Defects (SWR Alert LED Fix)

There is one known factory defect for which Galaxy has posted a fix. This involves the SWR PC board. The front panel SWR ALERT LED will light when the actual SWR is below 3:1. There is no danger to the radio with the LED lighted. The only concern is that if the SWR should suddenly shoot up, the operator would not know since the ALERT LED is always lit. In order to fix this, you must locate C5 on the SWR PCB. Replace C5 with a 1/4 watt, 22K resistor.

and dont forget to replace Q17 (2SC1674) with a 2SC2999, or an NTE107 for a dramatic increase in the signal to noise ratio of the receiver.
(very noticable!)

not sure on the clarifier issue, but i would imagine that jumpering D38 would be for a slide increase, but im not sure.

good luck,
matt
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Canon5218
Junior Member
Username: Canon5218

Post Number: 33
Registered: 8-2006
Posted on Wednesday, September 06, 2006 - 7:21 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Read that thing about a hundred time Matt...haha I have it printed off. Before long I am gonna be an expert of the 959. =) Doing the 10kHz +/- mod this weekend and unlocking the clarifier.

I would like for Lon to respond on the D38 question.
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Tech808
Moderator
Username: Tech808

Post Number: 11083
Registered: 8-2002


Posted on Wednesday, September 06, 2006 - 9:03 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Cannon5218,

Unlock the Fine Tune Control!

Below is the modification I used to unlock the Fine Tune Control on CEF#100 / Ironmask's Galaxy 959 for him.

#1 ~ Remove R-113
#2 ~ Remove D68
#3 ~ Remove D-38
#4 ~ Place wire across D-38 mounting holes.
#5 ~ Place wire from J-14 pin +8V to J-9 pin F1

NOTE!
The same mod also works on the Galaxy 949.

This modification is from:
"MASTER-MODS" Volume 4

Hope this help's,

Lon
Tech808
CEF808
N9CEF
CVC#2
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2051
Registered: 9-2004
Posted on Wednesday, September 06, 2006 - 6:10 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

canon, you'll notice that i removed a couple of the mods that were in that section for my post.
the reason is that those mods are NOT GOOD for your radio. they are "money makers" for the truckstop techs.

if you do nothing else to this radio, replace the 2SB754, do the AF amp mod, and change Q17 to the 2SC2999.

i must admit that i am not a big fan of these radios, and its because of the receive. the transmit sounds great on them if they are not hacked and pushed to the limits.
the receiver is just very noisy IMO, and doing the Q17 change is a big step in curing that problem.
the diode changes help too.

good luck, and you can trust lon's info,
matt
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Canon5218
Junior Member
Username: Canon5218

Post Number: 34
Registered: 8-2006
Posted on Wednesday, September 06, 2006 - 6:07 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks for the response Lon. I was just wondering if you or anyone for that matter could tell me what the purpose of removing D38 is. The mod listed on CB Tricks is identical as the one you listed from Master Mods with the exception of removing D38...they do not list it.

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