Hi Richard,

Thanks for the quick reply. Actually I wasn't aware of the original
ratings, in fact until Tuesday night I didn't even know what the heck
L1 and L2 were on the circuit diagram (refer earlier comment about me
being an electronics ignoramus).

I got desperate (the sulphated batteries are in an EV and it's
basically useless until I recover them) and ordered the parts anyway.
I think they'll be ok.

I got the 200uH choke from Jaycar:
http://www.jaycar.com.au/productView.asp?ID=LF1276&CATID=&keywords=choke&SPECIAL\
=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=\
&SUBCATID=
and the 1000uH choke from RS:
http://www.rsaustralia.com/cgi-bin/bv/rswww/searchBrowseAction.do?Nr=avl%3aau&N=\
4294918384&name=SiteStandard&forwardingPage=line&R=0228551&callingPage=/jsp/brow\
se/browse.jsp&BV_SessionID=@@@@0405384956.1173848947@@@@&BV_EngineID=ccdladdkgih\
ljdlcefeceeldgkidhgn.0&cacheID=aunetscape

Based on what you've said they should be ok...I think. I'm not sure I
have much choice.

I also got the IRF9Z34N from RS:
http://www.rsaustralia.com/cgi-bin/bv/rswww/searchBrowseAction.do?obs=sObs&name=\
SiteStandard&No=0&N=0&Ntk=I18NAll&Ntt=irf9z34n&Nty=1&D=irf9z34n&Ntx=mode%20match\
partial&Dx=mode%20matchpartial&callingPage=/jsp/line/line.jsp&BV_SessionID=@@@@0\
405384956.1173848947@@@@&BV_EngineID=ccdladdkgihljdlcefeceeldgkidhgn.0&cacheID=a\
unetscape&Nr=avl:au

At least I know that bit is 100% correct.

My EV has 4 12V 50Ah AGM batteries so the voltage of C4 at 25V should
be right on the money since I plan to do each battery individually.
Speaking of money, I hope this works or I will be coughing up a *huge*
amount on some new batteries...

I'll throw a zenner in there too as you suggest. Thanks again!

I'm off to DSE (http://www.dse.com.au/) to pick up a pack of 1N4004
diodes as that was what was suggested to me to use for D1. I might
also get a board etching kit and have a go at making my own boards
using the traces from this site:
http://members.shaw.ca/pferlow/desulfator.htm

Cheers,
Ash

--- In randrdesulfatorforum@yahoogroups.com, "linesrg48"
<courtiestown@...> wrote:
>
> Ashley,
>
> As you're probably aware the original API-Delevan inductors were
> rated;
> 220uH was 2.025A
> 1000uH was rated 0.39A
> so this gives you a clue as to the 'minimum' you should be looking
> for.
> You can go above this, but as others more knowledgable than me will
> tell you, everything kind of impacts on everything else and a balance
> has to be achieved.
> I would look at what Jaycar or similar has or try looking at say the
> Coilcraft range (I don't know who might stock it in Aus) as they will
> have something to suit.
> You could go for 100uF/ 25V at C1 and anything up to 6,800uF for C4,
> the voltage arting of C4 should be at least double the battery
> voltage.
>
> For prtection youi should also put a 15V zener parallel to C1 to
> protect against spikes.
>
> Regards
>
> Richard
>
> --- In randrdesulfatorforum@yahoogroups.com, "Ashley" <tty07@>
> wrote:
> >
> > Hello, I'm glad to find this group as I've been reading the ezboard
> > web forum but it appears to be more or less deceased. I'm in the
> > process of building the basic, simple, original Alastair Couper
> > desulphator comprising 13 components.
> >
> > I either already have, or can order all of the components but the
> > chokes are throwing me for a bit of a loop. I've consulted with
> > someone much cleverer than I (I'm an electronics ignoramus) who
> > advised that two chokes I'd selected as potential candidates would
> be
> > unsuitable as they're only rated for 155mA.
> >
> > I can get the 220uH choke rated for 5A, and a 1mH (which I presume
> to
> > be the same as 1000uH) rated at 1.6A. Would this be sufficient? If
> > the lower current ratings will do that would be great because
> they're
> > significantly cheaper, but since I'm only making 4 it probably won't
> > matter that much.
> >
> > Also, will it be ok to substitute a 33uF 25V for C1 (should be 30uF
> > 16V) and 100uF 25V for C4 (should be 100uF 16V)?
> >
> > Any advice gratefully received.
> >
> > Cheers,
> > Ash
> >
>