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Steve's DFB1 build

Posted: 06 Apr 2022 21:20
by Steve
Allo all,

I'm gonna be building a DFB1 and doing some testing of the device in the coming weeks. I've got most parts on order so I'll add bits and bobs to this thread as I go.

So far all I've done is do the 100nf and 10uf SMD caps and the 33ohm resistors. I've been using hot air completely so far, I find it easier to use hot air and solder paste for SMD components.

Thanks @Badwolf for the super impressive work on this.

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Re: Steve's DFB1 build

Posted: 06 Apr 2022 21:28
by Steve
By the way - advice on getting cheap memory! Does anyone know where you can get cheap hardware to scavenge 64mb pc133 SDR memory chips from? I know it's fairly easy to find 512mb pc133 memory in the wild but they are usually two rows of 8, so 16x32. I can't seem to find anything that has 8x64 for instance - as this would be much cheaper than buying new old stock single chips.

If anyone has any advice let me know pls!

Re: Steve's DFB1 build

Posted: 06 Apr 2022 22:43
by Badwolf
Good luck, Steve.

The 64MB config isn't that expensive: https://uk.farnell.com/integrated-silic ... dp/2253829

We can always do a 32MB build if needs be too.

Worth pointing out that the 'MB' quoted on memory chips is megabits, by the way. Divide by 8!

BW

Re: Steve's DFB1 build

Posted: 07 Apr 2022 08:54
by mrbombermillzy
@Steve

If you can hold out till later today/tonight, I have several SDR modules (32-256mb IIRC) scattered around the house. :lol:

Re: Steve's DFB1 build

Posted: 07 Apr 2022 10:32
by Steve
Badwolf wrote: 06 Apr 2022 22:43 Good luck, Steve.

The 64MB config isn't that expensive: https://uk.farnell.com/integrated-silic ... dp/2253829

We can always do a 32MB build if needs be too.

Worth pointing out that the 'MB' quoted on memory chips is megabits, by the way. Divide by 8!

BW
Ok might just get from Farnell then, didn't realise they were so cheap there :)

Re: Steve's DFB1 build

Posted: 07 Apr 2022 10:52
by stephen_usher
The biggest problem with Farnell is that they add a massive handling charge in addition to the postage.

Re: Steve's DFB1 build

Posted: 07 Apr 2022 12:31
by Badwolf
stephen_usher wrote: 07 Apr 2022 10:52 The biggest problem with Farnell is that they add a massive handling charge in addition to the postage.
Who do we think the best is actually, guys?

I've never ordered from Mouser or Digikey as the overheads were just too great. I used to use RS but they really upped their shipping fees and had the worst selection. I now tend to use Farnell as I'm registered as a business user there and mostly it's just a £2 handling fee after that.

I geuinely wouldn't know who to recommend to someone who just wanetd a few parts every couple of months.

BW

Re: Steve's DFB1 build

Posted: 07 Apr 2022 13:01
by Steve
I find that mouser is good if you spend over £30 it's free delivery. But I don't know anywhere cheap for small items.

There is a company in the UK called littlediode.co.uk which I absolutely dislike as they list parts for massive markups. They list on eBay and all their parts do not have photos, if you check their website they all have massive lead times - so my theory is that they don't hold stock and just order everything from China in a kind of 'just in time' model. Avoid!

Re: Steve's DFB1 build

Posted: 08 Apr 2022 16:54
by Steve
Ohh look what has arrived :) hopefully have some more photos later!

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Re: Steve's DFB1 build

Posted: 08 Apr 2022 17:17
by Badwolf
Oh, whoops. Did I say 0805? I meant 2012s!

I hope you haven't ordered too many. Sorry about that. :oops:

BW































:lol: