Winter Hill receiver project

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Winter Hill

The Winter Hill receiver project by Brian G4EWJ with hindrance occasional help from Mike G0MJW. It uses the BATC Advanced receiver hardware.

The software will run on the Raspberry Pi4 desktop environment providing a multi-channel receiver capable of receiving up to four channels simultaneously.

Timeline

December 2020 - Currently the project is at the design phase with a proof of concept receiver working on breadboard hardware.

February 2021 - beta testing in progress

March 2021 - First production PCBs expected

Hardware

The PCB design by Mike G0MJW is based on a completely new concept, BATC Advanced DATV Receiver, supporting two SERIT tuners with an integrated Raspberry PI4 and PICs. No USB module is required. This supports 4 simultaneous receivers in either a set top box mode, with the PI desktop, or headless, or a combination of these.

Version 0.1

Feasibility design which worked fine

Version 0.2

A prototype that was also built by several beta testers. Two pin programming jumper instead of 3 pin and didn't fit in the box.

Version 1

First general release PCB - Likely release March 2021



Software

TBD

Hardware Build

Boxed


Schematic is here: File:Winterhill.pdf

BOM is here: File:Winterhill BOM.xlsx

It is best to build this in order of component height. It took the author about 3 hours. There is an old proverb, a man with a watch knows the time. A man with two watches is never sure. While working with SMT, if you make a mistake, having two soldering irons to had is a great help when removing misplaced components. The other essential trick is to have the right tools for the job, a fine tip iron and thin, ideally 0.3mm solder. With experience you can use bar solder and a poker, but you are on your own there. Plenty of light and magnification is a must. If you don't have a magnifier then some +2 or +3 reading glasses might help those with normal vision.

Step 1

Starting with an unpopulated PCB fit all the parts shown, Resistors, Ceramic capacitors, Diodes, Inductors:

Low profile parts

Step 2

Next fit the 2 PICs and 4 LEDs - ideally use IC sockets for the PICs.

Higher

Step 3

Next fit the Electrolytic capacitors

Caps that are not bipolar

Step 4

Now fit the pin headers and fuse holder:

Pin Headers

Step 5

Then the DC jack and remaining headers EXCEPT to PI GPIO header.

More Headers

Step 6

Next the regulators and ferrite chokes:

Regulators and Chokes

Step 7

Now for the PI GPIO header. This requires thought and care. It needs to be at the correct height above the PCB and that depends on how you plan to mount the PI and if it has a heatsink case or not. Test fit the header to the PI and mount the PI on the PCB, then the header will be in the correct place. Removing the header afterwards is almost impossible without damaging the PCB so take time to get this right. Best now remove the PI to prevent damage, or treat it with care if you choose not to. If it is in the metal case it will probably be fine.

GPIO Header3D view

Fit the fan if required.

GPIO Header

Step 8

Once that's done it is time to power up and test the voltages are correct. It won't work if you don't fit the fuse. Ideally use a current limited 12V supply and pay attention to the current, - there should not be any. Make sure the JP1,2,3 jumpers are open. Check for correct voltages and fix if not.


Step 9

If all is well fit the NIM(s). Make sure they are properly seated. Do not use a socket if you want the board to fit in the recommended case, there is insufficient clearance and it won't fit.

Completed boardNIMs

Testing

The board is now ready for testing. First fit the PI4 and jumpers JP1, JP2 and JP3. If you test it outside the case use no more than 12V, otherwise U2 will get hot. It needs to be heatsunk to the case. So does U1 if you plan to use it. The current should be under 1A.

If all OK, go to the software installation section. The PI OS needs to be loaded and the PICs need to be programmed.