Schematic For Echostar AD3000ip Power Supply

[scooby12]

llews

the supply code was d1k5 2w res 1k5 they also have a chart that works out the value if the colours are orange , yellow ,black , yellow , yellow the value works out at 3400000 hope this mean anything to anyone

cheers

 

[Llew]

No. 1k5 is 1500 ohms. You needed a 15k - 15000 ohms. Hence the quick death.

You may now need to check Diode D1 for possible damage.

 

[scooby12]

tried again d1 looks ok and put in 22k resistor could get a 15k still get intermittent power ups the dot keep going round and round and sometimes works any pointers

cheers

 

[Llew]

First culprits to check are the electrolytics. Plenty to choose from, but the ones across the 5V supply (C16,17) work hard. But if any show signs of failing - tops bulging or generally look in a poor state, replace them.

Llew

 

[patdiamant]

Can't see a Q6 (?)

Hi Llew,
On my Praxis Digimaster 9800CI receiver (same as AD2000) I have Q6.It is a PNP transistor (A1266) between Q2 and Q5 on your diagram. Then Q5 is a power NPN transistor (D2058). </p>Thanks for all your tips about this smps. </p>

 

[Llew]

Nor could I - it was never used (at least on my supply - I did confirm this in an earlier post)

Llew

 

[vlammie]

Hi Llew

I finally have my AD3000 power supply working again. The problem was indead not on the primary side. I replaced IC1, but this did not solve the problem. I decided to solder out all the elco's on the secondary side and as you already suggested, some were bad. C23 was halve the original value (22 microF) and C16 had only 1600 microF left. Measured with a standard multimeter. So I can not predict there behaviour for the AC pulses they see when working in the power supply. I ordered replacements and finally the device works correct again. I tested the 5V digital output till 6A load without any problems. Voltage with this load was still about 4.5 V. Regarding the active device list i have found some differences. Q2 was 2SC3198, Q3,4 was 2SC2328 and Q5 was 2SA1273. IC2,6 and 8 were L9946. I also found another hot spot on my printed circuit bord. This was caused by R17 (1k, 1/8 W). This one seems to be a little small for this place. Replaced it with a 1/4 W type. R3 is 2 W in your list. I suggest to use a 3 W type on this spot. On your diagram I think C44 and C46 are swapped. I also could buy a second hand power supply from somebody in the Netherlands, who got it directly from Echostar in the Netherlands as a replacement unit. It has exactly the same hot spots around R3 and R17. Hopefully it won't break again soon. But now at least I have a spare part.

Thanks again for your support, tips and suggestions. If I can be of any help, please let me know.

Let it "burn" again forever )(-red

 

[Llew]

Hi vlammie

Glad the supply is doing its job again.

Better to use an ESR meter on PS caps, as even when showing good capacitance its series resistance can be too high, losing its DC smoothing efficiency.

Yes, manufacturers sometimes use alternative transistors etc. when the original type becomes unavailable. Q5 is indeed a 2SA1273, my mis-type. Will correct the list.

Thanks for your suggestions on R17 and R3, true R3 could benefit a larger wattage, just that space constraints on the board limits size, although with mine, I extended the legs to raise it above the board.

C44 and C46 safety resistors have the same value and do the same job, but well spotted! but I'll leave the diagram as it is unless it becomes necessary to change anything there any time later.

Enjoy your revitalised Echostar!

Llew

 

[vlammie]

Thanks for your suggestions on R17 and R3, true R3 could benefit a larger wattage, just that space constraints on the board limits size, although with mine, I extended the legs to raise it above the board.

Llew

Hi Llew

Thanks for your tips for measuring elco's. ESR meters do not seem to be very common. I see a lot of home made devices in the internet. The values you get seem to be a little bit arbitrary. In fact you should now the manufacturers specification to be able to judge wetter or not a reading is acceptable.

Talking about R3. I have used 3W devices, which are a little bit larger as the original 2W types, but mounted them in a different way. I have stuck the body of the resistor in the opposite hole and have the bended lead in the hole were the body normally is. In this way it is much further away from C3 and C12 and has more room to "breath".

I also discovered that my back up SMPS was actually not switching off the switchable voltages (21, 30, 8 and 5 V) due to a defect transistor Q5 . This device had a shorted CE. The receiver however worked okay and looked swiched OFF were actually the voltages were still ON. (clock in display). I did not measure the power consumption but this might be much higher then when the switchable voltages are really OFF.

Transistor Q5 (2SA1273/2SA928A in my devices) seem to be dimensioned to narrow. Vce max. for these devices is 30 V. In the OFF stage however the voltage accross collector-emitter is continously more then 30 V. The SMPS is still switching to keep the 12 V and 5VS line "live". So Q5 will continuously see more then 30V across CE.

I have replaced this transistor for a BD229 which i had laying around here. This device can withstand higher CE voltages, although Ic max is a little bit lower (1.5A versus 2A) But I don't expect currents that high in the 30V line.

Hopefully I don't need my spare soon, but you never know. The devices get pretty hot and this is indead not very good for the lifetime of the elco's. I might have to replace some more soon. But for now I am a happy AD-3000 viewer again.

 

[Llew]

Surely with T5 off, no current is being drawn, so the collector will be 0V referenced to chassis via the load through the 30V line. This gives you the >30V reading as that supply is off load.

My home-made ESR meter can be seen here (post #31) -

http://www.satellites.co.uk/satelli...ery-satellite-hobbyist-should-have-one-2.html

Llew

 

[patdiamant]

Echostar used to be affiliated with Hughes Tracker Systems, later HTS, so there is a chance a decent stab with Google will bring up the other PSUs.

Hi Channel Hopper
Houston Tracker Systems, HTS, Echosphere, Echostar, DISH Network, are in the same family. (Not Hughes ...)
HTS receivers had often failures in their SMPS. I had repaired mine many times.</p></p>

 

[vlammie]

Hi Llew

My SMPS broke down again. This time C10 shows a hard shortage. It blow the fuse.

Lucky i have a spare SMPS now. Replaced it but then discoverd that the motor was not rotating in 1 direction. I got a "motor error". After investigation i discovered that a trace on the PCB runs close the the metal mounting stud inside the receiver. This trace is running from the connecter to one of the relais. This trace is then shorted to ground and the motor is not moving anymore. I have taking of a part of the stud and this solved the issue.
Furthermore I think the east relay is drawn in the "activated" position instead of in the resting position. During the initialisation fase of the receiver (ON) both relais are activated for a short time, bringing both M1 and M2 to 36 Vdc. This results on no movement of the motor. Normal only the east or west relais will be activated, switching eithere M1 or M2 to 36 Vdc and leaving the opposite connected to ground.

 

[Llew]

You're absolutely right, vlammie. I just drew the diagram 'as is', without regard to the position of the contacts. I'll correct it in due course.

Thanks.

 

[Sixoence]

Hi - Have an AD3000 and stumbled across this thread. It's currently OK. I have a spare PC PSU fan that seems could help the cooling from earlier postings. Can anyone advise on how this should be installed to that I have a chance of lengthening the receivers life. My electronics knowledge is basic although have a soldering iron, which I've used with varying degrees of success.

 

[Llew]

You can connect it to the 12V supply (one wire to connector CN2, 6 wires from the left on the mainboard), and the other to any chassis point).

I used this method with a CPU cooler fan (4cm) mounted upright to the middle mainboard screw with a small 90 degree angle piece fashioned out of a strip of metal.

This gave a good airflow by sucking in air from the RH vents , across the CPU and SMPS and out through the LH vents.

A larger fan would probably have to be mounted under a vent in the top lid (preferably the one above the SMPS).

Llew

 

[Sixoence]

Many thanks Llew - I have a 9v cooling fan from a laptop, but its only 2.5cm. It will mount nicely to the right of the CPU. Are there any 9v supplies available????

 

[Llew]

There's an 8V supply on pin 14 of that connector, but there may be some back EMF from the fan that could kill the Q4 transistor. Better to use the 12V supply with a resistor to drop the voltage. Value would depend on the current taken by the fan - haven't got one of those, but it'll only be a few mA. May be a spec somewhere online.

Llew

 

[Sixoence]

Thanks - by virtue of my eyesight, I've stated the wrong voltage. It's a 5v fan drawing 0.09 Amps. Don't suppose there's a 5v supply in there?

 

[Llew]

Yes, the main 5V supply is on pin 5 from the left of the connector (CN2 is the block on the SMPS by the way, I'm referring to the mainboard connector, may have misled you there).

 

[Llew]

I should mention that it's quite easy to just prod a thickish wire into that connector pin, wire and tape it to the fan lead (they're usually too small to do that) and secure it to the other wires with a small plastic tie - saves soldering. I used that method with mine successfully for the many years I had it running. I don't have one in mine now, as I only use the box for its positioner.