So here is the complete lowdown on parts:
RFParts MRF458:
$49 for 2 unmatched "low beta only"
$59 for 2 matched Motorola
Ebay MRF454:
$70 for 2 unmatched ---- china parts are marked "refurbished' not new,
which kinda makes me take pause.
RFParts MRF454:
$90 for 2 unmatched
$96 for 2 matched
TenTec "Custom made gain and gain-range matched MRF 454 pair"
$125 for 2
So go cheap (ebay), rebuild to original (matched) or upgrade an aging rig
and reward the company that still supports 32 year old gear.
Humm, bummer
Remember, that Paul needs to mark up the price of his parts, too
Does RF parts carry the MRF454s?
I've had great success using my weller WTCP iron with a 35 watt element and
a large chisel tip.
and you need lots of solder wick.
the two emitter leads are the hardest as they are mounted to the largest
amount of copper on the pcb
you didn't say what kind of mount they have, but since I don't have a thing
to do but lay here on the bed with the iPad, here's what's on ebay
$35 each Plus free shipping... from china of course!
http://www.ebay.com/sch/i.html?_odkw=MRF454&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0&_nkw=MRF454&_sacat=0
Mike, WB8VGE
SunLight Energy Systems
The Heathkit Shop
http://www.theheathkitshop.com/
J e e p
o|||||||o
A man with one clock knows what time it is. A man with two clocks is never
sure.
On Oct 15, 2013, at 5:30 PM, Paul Harker wrote:
> Try as I might my old Ungar iron and roll of SolderWick fight a losing
> battle against the leads. I've got a 70W digital-control solder station so
> I ordered a much heftier chisel tip element for it. The elements I have
are
> only good for tiny surface-mount chips.
>
> Replacement transistors will be my next issue. Unmatched MRF458s (per
> Mike) at about $50, matched at about $60, or matched MRF454s (per Paul at
> TenTec) for a whopping $125.
>
> The 454s have higher current/power ratings and slightly higher gain at
some
> frequencies. These are what TenTec uses for in-house repairs.
>
> Decisions, decisions...
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
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