Author Topic: DSX MOUNT  (Read 1485 times)

ivirlocri

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Re: DSX MOUNT
« Reply #15 on: January 22, 2018, 11:54:57 PM »
there are hard to find those regulators with 8 leads, its U2 , there are in green laser too ,U2 i know that is location on the board , there are also STK voltage stabilizators , on the DSX board is 78C12 or 78l12 , cant read all numbers and letters i see only first two num, 78 , the other numbers i guesing only
yes i burned all board , maybe are NDS drivers , i dont think that is PIC control burned it has protections of guys like me ,
AUTOSTAR is sending signals to the motor control board , but i lose the signals around NDS drivers or maybe Q 3 leads are burned ,
PIC control is protected with W1 , W2 , W3

nontpremlapi

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Re: DSX MOUNT
« Reply #16 on: January 23, 2018, 02:33:05 AM »
this mount was driving 8kg , with no problem , and its a gift , thats why i want to make it functional again

tingranseattters

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Re: DSX MOUNT
« Reply #17 on: January 30, 2018, 12:19:54 AM »
Gday Shaula
<p class="citation">Quote

i dont see mine telescope model in the AUTOSTAR menu , data is lost or AS cant read it from board
[/quote]
On connecting to a mount, the Autostar asks the PIC on the RA motor card what type it is.
If it gets no reply at all, it declares "Motor UNIT Fault"
If you dont see that when booting up, then the PIC is responding at least.
The response to the "what are you" command can be one of about 8 motor card types, and the models that get presented by the handbox will be filtered to suit.
Best bet is to buy a second hand board, but if you want to try and fix what you have, there are several circuit diags for the Meade cards on the site.
ref https://www.cloudyni...rive-the-lx200/
The motor control uses a simple HBridge drive so its a matter of chasing the signals to see where they go.
The HBridge uses twin PChannel mosfets for the high sides, and these are switched fully ON or OFF using transistor switches on the gates.
The low side also uses a twin NChannel mosfet and this is driven using PWM, ( normally supplied via a quad And gate driven from the PIC, but the DS looks like it also uses transistors, based on above thread )

Andrew Johansen Melbourne Australia

akbrevecop

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Re: DSX MOUNT
« Reply #18 on: January 31, 2018, 02:44:50 AM »
thanksSurveyor 1
this is second time i switch the wires + - to supply power. First time i get that notification MOTOR UNIT FAULT , but i fix the problem and start to work ,
But this time or second reswitch + - , i dont receive the message MOTOR UNIT FAULT ,simply motors dont run , but sometimes when i power on with no connected autostar motors are runing on max. speed by it self
I see ETX models , LXD models , DS models , but mine DSX all DSX models are lost in the AUTOSTAR , i cant find NDS9956 and NDS9953 to replace it , for tranziztors its easy , but i dont know are they PNP or NPN , so far i can see 1p3 on all transistors same marking , also there are a lot of burned circuit lines on the board , the scope is old about 12 years , only thing i know for old type of transistors if the last number is 2,4,6,8 its PNP , if its 1,3,5,7,9 its NPN
sorry for my bad english i hope you will understand

ceisilipan

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Re: DSX MOUNT
« Reply #19 on: January 31, 2018, 09:06:23 AM »
Gday Shaula
If you dont see "Motor Fault" when booting, then the RA card is sending "something" back to the handbox.
If you are only seeing ETX, LXD and DS models, that means the detected motor card is not one normally allocated to a DSX.
There are three groupings for model selection
1) The (early)ETX, DSX and DS2000 series are grouped to a type x0C card
2) The std ETX,LX90,LXD75 are linked to type x15 or x25 cards
3) Then there is the rest

As you are part of "the rest", it becomes harder to diagnose, unless you have patched firmware ( in which case wee can peek whats coming back )

<p class="citation">Quote

i cant find NDS9956 and NDS9953 to replace it
[/quote]
The standard MOSFET units used on later boards were the Vishay Siliconix 4936, 4947
If you google "meade vishay 4947" or "meade vishay 4936",
you will also get some more feedback on others who have hit this.

Andrew Johansen Melbourne Australia

Ryan Lawlor

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Re: DSX MOUNT
« Reply #20 on: February 02, 2018, 11:55:45 PM »
can i replace the voltage stabilizator 78L05 with standard one 3 pins or leads , because original part has 8 leads or pins , also Autostar works even without stabilizator put on the board , i remove it couple of times
THANK A LOT

Alex Manuel

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Re: DSX MOUNT
« Reply #21 on: February 08, 2018, 05:52:21 PM »
Gday Shaula

Re the voltage regulator, not sure.
The 8 pin unit may simply have all the stabilising capacitors inbuilt, but at the end of the day, you only need a solid 5V bus on the card.

Andrew Johansen Melbourne Australia

synchanrimyp

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Re: DSX MOUNT
« Reply #22 on: February 09, 2018, 08:52:59 AM »
how 5 v , because main voltage is 12v , i always get 12 v on measure instrument , , you can see images up some are mine , ones with no 8 leads regulator ,