Schematic For Echostar AD3000ip Power Supply

[Llew]

I've drawn up a circuit diagram for the SMPS of this receiver. More for my own curiosity and not exactly of professional quality, however it shows all components including positioner relays etc.

It might come in handy for circuit tracing in the (likely) possibility of a fault occuring in the power supply.

Here's a list of the main semi's -

TR1- BT137 Triac

IC1- 1H0565 Power Switch

IC5- Power Switch (for motor drive)

BD- PBS606G Bridge Rectifier

IC2,6,8- L9941 Optocouplers

IC3,4,7- KA431 Prog.Shunt Regulators

D5- SB860 Schottky Diode

D13- U16C20 Power Rectifier

D16,17- P6KE6.8A Transient Voltage Suppressor

Q1- IRFZ24 Power Mosfet

Q2,Q7- 2SC945 NPN Transistor

Q3,Q4- 2SC3205 NPN Transistor

Q5- 2SA1273 PNP Transistor

Can't see a Q6 (?)

(R3 is 15kohms - often discoloured and unreadable visually due to overheating.)


Llew

[Llew]

Oops, forgot to put the fuse in


Llew

[nopfusch]

great job, Llew

Only if one has done this job , knows what patience is required. I talk from
experience ...
May I send you a receiver.............???????????
Just joking,
keep well
nopfusch

[Jeff_19341]

Hi Llew

Did you get a stiff neck drawing that superb diagram? I got one reading it!

[pgh13]

[QUOTE=nopfusch]great job, Llew
'ere, 'ere

[Llew]

Hi Llew

Did you get a stiff neck drawing that superb diagram? I got one reading it!

Well I just took a photo of the print side, making sure the light brought out the copper lands, printed it out and drew along the circuit checking it against each component. Took a few hours including checking online for component identification. Once you start these things I suppose it becomes a bit of an obsession - I won't be doing the rest of the STB though even if I could

Hard to find schematics for Echostar stuff. Saying that, someone's bound to find one for this

great job, Llew

Only if one has done this job , knows what patience is required. I talk from
experience ...
May I send you a receiver.............???????????
Just joking,
keep well
nopfusch

No please don't - I value my sanity!

Llew

[workshoppete]

Nice to see a proper circuit diagram instead of all these confounded block IC's that tell you nothing about how a circuit works. Great work Llew.

[Burnham Beech]

Thanks for going to the trouble - I appreciate it, for one. My ad3000 has survived up to now, but it has lots of dodgy moments.

I have never seen any ad3000 circuit diagrams published and my suspicion is that echostar don't have the copyright. I assume that the Korean manufacturer holds that (were they called hanhan or something similar ?).

I know that echostar in Holland were able to issue the complete circuit diagrams for the LT8700 - which echostar both designed and manufactured.

[Llew]

Yes I have the LT8700 SMPS schematic, wish I'd had it when I had an obscure fault in the motor drive some while back. A lot more complicated than later models.

Of the AD3000, can't make any sense of the circuit coming off of D7 in the secondary supply. I think I may have Q4 wrongly 'wired'. Will check it out.

Llew

[Llew]

Checked the D7/Q4 configuration, it's correct as it stands. It's not feeding any voltage supply circuit, all Q4 does is turn off when in standby. PCS (S/by line) turns off Q4 via Q2, Q5 and the aforementioned supply goes high (8.5V). For what reason I don't know.

Tip: If the PCB warps slightly (heat?) you can lose the chassis earthing point (top left, looking from the front - the two blue capacitors which connect to an isolated earthing strip). You can easily see if this has happened by checking the board contact point through the side of the chassis. It happened with mine, I had to insert a small piece of metal to secure a good contact. Without this earthing, these capacitors are ineffective and may cause noise on tne mains line.

Llew

[Channel Hopper]

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.

[Llew]

Beleive me I tried CH. The only other PSU I found was for the Echostar 3000 - a different beast entirely (US model).

Llew

[component1]

Llew,
Thanks for the excellent work you did on drawing the power supply for the Echostar AD3000ip. I have now been able to repair a friends' receiver without having to laboriously go through the task of mapping it out which is very time consuming as I have done this before.
Two faults were located.
1. Motor error caused by a faulty M Pulse diode D16. This is a P6KE6.8A Transient Voltage Suppressor for future reference (so is D17).
2. A fault in Q4. This was a 2SC2328A in my machine which I was able to replace with a 2SC3205. The 2SC series are getting harder to get hold of these days.

There was a small difference with your drawing. The emitter of Q4 went to CN2/14 and not direct to earth on this receiver.

Many thanks again

[Llew]

Thanks for that component1!

Of course! I thought there was something odd about that supply circuit in my drawing. It's obviously the 8V line All becomes clear now. Should've checked more closely.

Cheers again for the extra info. Glad it was of some use - will alter diagram.

Llew

[Llew]

Ok, changes made to original schematics.

Llew

[>COR<]

Well done M8!

Lots of us still running the old beast ( AD 3000 IP)

Bought mine new, added computer fan then because i thought it was too hot.
Seems it was an good idea, keeps the reciever cool including the PSU/cams.

Just an dust cleaning to do once an year

[Llew]

Yes >COR<, I added just such a fan (in the middle of the board) when I first had the box. With a thermistor circuit added to vary the fan speed according to the heat generated.

Llew

[Llew]

Two errors in original diagram 1 have been corrected. R22 added in PCS standby line

R18 now goes between Q5 collector and Q3 base.

Llew

[>COR<]

Thanks for the corrections m8.

To add to my older post, i also added old heatsinks with cooling paste to the memory chip and cpu, and all hot i.c.'s
Since the reciever is on much of the day here, and goes with us to France in the holliday season, it has performed well, must have travelled 10.000 miles by now

Cheers,

Cor

[Llew]

Apologies for the mistakes >COR< I was taking some voltage readings and noticed the discrepancy.

Great to hear the old box is still giving of its best. I have a small fan positioned vertically between the processor and SMPU, giving a good air flow across the board, shoving it out of the lefide vent of the box.

Regards, Llew

[>COR<]

No appologies needed m8, just an thanks to you for your excellent work on the reciever
Think it still does an very good job, not planning on parting with the reciever yet, running my actuator fine with the 1.1 Triax dish from 50 east to 50 west.

I put the fan on top of the PSU then, took out an section of the top cabinet and blow the air in, cleaning the reciever once an year of dust.

Inside stays absolutely cold, reduced the rpm's of the van with an small resistor in the + lead feeding it from the +12 volt line on the back.
The only design flaw they made was to block the airflow from the underside of the cabinet to the top with the PCB.
This way they made the reciever no airflow could be possible from the underside to the top.

This causes the PSU to heat up too hot, caps loosing their fluid and break down, as well some makes of the memory chip wich were an bad batch to go prematurely.

The cooling with fan and heatsinks solves those problems.

Use ballbearing fan, these last the longest.

Cor

[Tony Kightley]

Thanks, Llew, for the excellent circuit diagram. My receiver has suffered failure of D16 and D17, which are easy to deal with - though procuring relacements might not be easy. Cricklewood has P6KE180A which I will need to check to see if it is a suitable replacement.
However, the 'hot spot' you refer to under R3 is bad. But, worse, the colour coding on R3 is yellow, yellow, black, yellow, yellow. The value measures as 18.8k which is, obviously, wrong and, so, it must have risen in value due to intense overheating. (In fact, I suspect the yellow bands may, once, have been orange!) So, please can you let me know the value of R3. I guess it is 33 ohms. Thanks.

[Llew]

Hi Tony

R3 is 15K - I did reply to a similar query earlier, I'll add the value of that rogue resistor to my original post! -

http://www.satellites.co.uk/php-bin/forum/showthread.php?t=70698

Yes, difficult to find those suppressors; like yourself, have to check on replacements.

Llew

[Tony Kightley]

Thank you, Llew, for the resistor value. Yes, it gets quite hot, not surprising with almost 200v AC across it. Luckily, I have several 15k WW resistors of Painton make, from when I worked for them over 40 years ago. They are rejects for appearance, but electrically sound. They are 5w glazed types. If anyone reading this would like one as replacement for their hot, 1w type, I will send them one if they e-mail me at tkightley*tiscali.co.uk

[Llew]

Hi Tony

Yes, excellent resistors, used to use them in HI-Fi projects in the '60s.

My only caveat in using high-value wirewounds in switch-mode supplies would be their self-inductance, although granted it will be in the LF side of the supply.

I assume they are bifilar wound though, so maybe they'll be suitable.

Llew