BATC Forum

Hi all
I have ordered (and received) an Adalm-Pluto (PlutoSDR) from Mouser UK.
As often happens, I found out afterwards that I should have ordered a better TCXO at the same time as delivery is stupidly expensive (£12 for a £3 item) unless you spend over £50 or some such figure, at which point it is free.

If anyone is doing a Mouser order would they mind ordering me one of these and post it to me?
https://www.mouser.co.uk/ProductDetail/ ... X13C40I05T

I will happily pay up front via paypal or bank transfer for the postage and item, the item costs £3.16 so hopefully £5 should cover the price of an envelope and a stamp.

Many thanks for reading

de Greg M0ODZ/2E0HIS/M6LWY

As a matter of interest

Why do you want a "better" TCXO? The existing one is entirely adequate for DATV, it may even be better for phase noise than alternatives. The same goes for LNB references for QO100. For DATV you are usually better off a low phase noise crystal oscillator unless you use an external LO to move the IF.

These arguments don't apply to the narrow band QO-100 transponder, but this is BATC.

Mike

Hi Mike, thanks for replying, and for the question.
Why would I change the TXCO? Mainly because I can't leave stuff alone for more than 5 minutes

I do intend to work both BATC and QO-100.

My local ATV repeater is inaccessible from my position, I need to hike up a hill to connect to it so getting things tested and working on QO-100 means I can then head up the hill with a bare bones system and (hopefully) get things working out of the box so I can have QSOs with BATC members at will.

Hi Greg,

I've one here spare can send over, is your address correct on QRZ?

John GI7UGV

Hi Jon.
QRZ has the correct address.
Let me know how you want paying

https://batc.org.uk/shop/5-donation-to-batc/ once it arrives is fine, in the postbox now

Jon you are an absolute star

As soon as it arrives I shall show the receipt below

No need and you'll be cursing it when you see how small it actually is.

There's two in the bag, the loose one was my first messy attempt so just bin that one, hopefully you get right first time unlike me

g0mjw wrote: ↑

Fri Dec 13, 2019 4:11 pm

As a matter of interest

Why do you want a "better" TCXO? The existing one is entirely adequate for DATV, it may even be better for phase noise than alternatives.
...
Mike

and

gi7ugv wrote: ↑

Sat Dec 14, 2019 3:40 pm

....
I've one here spare can send over, is your address correct on QRZ?
....

Mike - I'm curious as to whether it is possible to determine the phase noise of the Rakon used in the Pluto, and to do a direct comparison between it and the Abracon that John has substituted? From what I've read, the Rakon was chosen to meet AD's jitter requirements (<0.3ps IIRC)... And Rakon don't actually specify the PN. Abracon do specify the PN for their device, but do not mention jitter - Are phase noise and jitter related in any simple way such that they can be converted between?

John - I take it that (dodgy soldering exploits notwithstanding) you had/are having no problems with the Abracon, and it's performing well as a replacement?

Also, as I understand it, any basic inaccuracy in the oscillator's frequency can be calibrated out in the Pluto setup, so as long as the operating temperature is reasonably stable, the frequency shouldn't shift too much anyway... Is this thinking correct?

John, G8PEF

They are related. Phase noise is instability in the frequency domain, Jitter is variability in the time domain.

See here for an explanation and how to go from one to the other: https://www.analog.com/media/ru/trainin ... MT-008.pdf You might wish you hadn't asked...

Mike