Portsdown hardware update

Discussion about this major DATV Project. See also https://wiki.batc.tv/The_Portsdown_Transmitter
g8gtz
Posts: 987
Joined: Wed Apr 07, 2010 6:26 pm

Portsdown hardware update

Post by g8gtz » Wed Jan 18, 2017 10:43 am

The hardware design for the Filter Modulator card (the only custom hardware) is almost finished and I have updated the Wiki with the following information. There will be a number of ways to get a Portsdown filter modulator board.

Built boards

Once the design is finalised, built and tested Portsdown modulator boards will be available from the BATC shop and will just require the fitting of the supplied 5v regulator - a normal leaded component.

This is the easiest way but there will be a delay whilst they are manufactured and tested - in particular Chinese New Year starts in 2 days time and ends on February 4th which means they will not be available before the middle of February.

Roll your own

For those wanting to construct the board themselves, the blank PCB will also be made available from the BATC shop - there will be a small quantity of blank boards available as soon as the BoM is finalised, which may be this week.

We will publishing a bare bones parts list, or Bill of Materials, as an .xls file which you can upload to Digikey - you then simply checkout and pay Digikey and it will automatically order all the parts you require to construct the board, which will arrive bagged up marked with circuit references. This is the recommended way to order your parts if you decide to build the board yourself.

Or if you prefer to do it the hard way, a full parts list will also be published on the wiki and you can then order the parts from your own supplier.

We will be putting up more information as we finalise the design but to get you started the board layout has just been put on the wiki at https://wiki.batc.tv/Filter_Modulator_build

Enjoy :-)

g8gtz
Posts: 987
Joined: Wed Apr 07, 2010 6:26 pm

Re: Portsdown hardware update

Post by g8gtz » Wed Jan 18, 2017 5:44 pm

One important issue has just come to light.

It is possible to buy ADF4351 modules with a 10 or 25 MHz reference oscillator - the software is currently designed to control units with a 25 MHz clock. It may be possible to change this to select oscillators but if you are considering buying one in the near future it may be best to buy a module with a 25 MHz clock.

If buying from ebay, the description should include the reference frequency as seen in this example which, if delivered as described, is the correct item (caveat emptor) http://www.ebay.co.uk/itm/35M-4-4GHz-PL ... 4d48995cfc

73
Noel

g0mjw
Posts: 603
Joined: Sat Sep 20, 2014 9:15 am

Re: Portsdown hardware update

Post by g0mjw » Wed Jan 18, 2017 6:27 pm

I think most of them are 10MHz. Most of mine are as that's the common standard for GPS references. It's only a minor software change to deal with it.

Mike

g8gtz
Posts: 987
Joined: Wed Apr 07, 2010 6:26 pm

Re: Portsdown hardware update

Post by g8gtz » Thu Jan 19, 2017 9:01 am

We will add it to the (very long) to do list! In the meantime we suggest people buy the 25 MHz version, which does actually seem to be the more common, particularly if you buy the recommended black PCB module.

BTW - Portsdown is deliberately an open source project and all the code is on Github so if you and others with the right experience fancy helping out I'm sure the team would appreciate it :-)

Noel

M0SKM
Posts: 178
Joined: Sun Jul 13, 2014 3:15 pm

Re: Portsdown hardware update

Post by M0SKM » Thu Jan 19, 2017 11:43 am

g8gtz wrote:We will add it to the (very long) to do list!


Good news.
I've built five projects using the ADF 435X boards (three for me). Four using the green 10MHz boards and it's a 10MHz that's reserved for Portsdown.

No problems with wrong chips and a much sturdier board than the black board.

Well done to all the project contributors.

Steve

G4KLB
Posts: 199
Joined: Wed May 28, 2008 10:46 am

Re: Portsdown hardware update

Post by G4KLB » Thu Jan 19, 2017 3:53 pm

I have one with a 10MHz clock that's working fine with a new file from Dave, so don't worry if you have a 10MHz one.
If you plan to buy one now, It would make sense to buy the 25MHz one.
Its planed to have a console menu option to select either in due course so this advice may soon be irrelevant.

g0mjw
Posts: 603
Joined: Sat Sep 20, 2014 9:15 am

Re: Portsdown hardware update

Post by g0mjw » Thu Jan 19, 2017 6:44 pm

Good advice. Even if you have the wrong one, if that's possible, they are only £20 and they make extremely useful test sources.

Roberto48
Posts: 17
Joined: Fri Jul 06, 2018 2:04 pm

Re: Portsdown hardware update

Post by Roberto48 » Fri Oct 12, 2018 10:34 am

Hi,

Is it possible to change the ADF4351 clock freq in already installed Portsdown software? I'm using an x-tal of 30 MHz.
If so, where can I do that?

73's
Rob PA0RWE

g3zgz
Posts: 39
Joined: Thu Jul 16, 2015 1:36 pm

Re: Portsdown hardware update

Post by g3zgz » Sat Oct 13, 2018 7:37 am

Rob,
For older software there is an option to change the ref frequency via the console mode.
In the newer (not sure how long it's been there) software there is a touch screen menu option.

Click Menu2 at the top right
Click Menu3 at the top right
There is now an option to set ADF ref frequency on the right.
For your 30MHz you will need to change one of the Ref1,2 or 3 frequencies.
Click the set ref(x) button, use the <= button to clear the current value
Enter your frequency as 30000000 and press ENTER.
Click use the ref (x) and it will turn green.
Your Portsdown now uses 30MHz as the ref frequency.

I'm using my PLL board with a 12.8MHz TCXO from an old UHF transceiver and it works really well!

73

Dave
G3ZGZ

Roberto48
Posts: 17
Joined: Fri Jul 06, 2018 2:04 pm

Re: Portsdown hardware update

Post by Roberto48 » Sat Oct 13, 2018 11:55 am

Hi Dave,

Thanks for reply. Very nice option in the PortsDown software!
But... I checked it with 10 and 25 MHz and that is working OK, but not at 30 MHz.
The frequency output is too high (175.8 MHz) at 146.5 MHz setting (not calibrated).
It seems that the xtal ref frequency could not be higher than 25 MHz.

I hope you can 'repair' this!

Thanks,

73's Rob PA0RWE

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