Long ago I removed all adjustable voltage supplies from the shack because a
bump or a grandchild can break your heart(cook your transceiver).
On Tue, Dec 5, 2017 at 9:44 AM, Jim Thomson <jim.thom@telus.net> wrote:
> ## You forgot to tell us that it was a 40 A 13.8 vdc, switching type
> power supply !
> Found it on U tube, where the vdc pegged past 16 vdc. Another fellow had
> his
> way over 45 vdc...and fried his yaesu. The u tube fellow says his did
> not have
> any over voltage protection built into it ! Since his was under
> warranty, MFJ will
> repair it..... but not the very expensive yaesu xcvr.
>
> ## Fuses on radios will only protect against excess current, not excess
> voltage. Your
> surge protector on the input of the 120 vac.. feeding the MFJ switching
> supply, will not help at all.
> The issue is the lack of over voltage protection in the mfj switching
> supply, and what ever caused
> it to crank out excess vdc in the 1st place... frying everything
> connected to it.
>
> ## Either replace with a better quality switcher from a different
> manufacturer, or use
> an analog supply, like a 50 A CCS astron.
>
> ## way too many issues with the MFJ-4245 switcher imo. if the supply
> bows up, who cares... but when the
> same supply blows up a bunch of expensive gear connected to it, then its
> a serious issue.
>
> Jim VE7RF
>
>
>
>
>
> From: Shon Edwards
> Sent: Sunday, December 03, 2017 8:42 PM
> To: Jim Thomson ; Amplifier Reflector
> Subject: Re: [Amps] MFJ products
>
> I know this isn't really an amp question, but I checked my email for
> mfj-4245mv and found this one. Last week, the current just took off.
> Fried a couple radios whose fuses didn't work. Also my surge protector
> didn't stop it from frying my radios. Any idea what caused this or how to
> fix it?
>
> Thanks!
>
> de Shon, K6QT
>
> Shon R. Edwards, MA, AG (Czech Republic)
>
> Amateur call: K6QT
> 1039 N 2575 W
> Layton, UT, 84041-7709
> USA
> Home phone: (801) 444-3445
> E-mail: sre.1966@gmail.com
>
>
> or
>
> Shon Edwards
> 715 Strawberry Creek Private Rd.
> Bedford, WY 83112
> Cell: (307) 248-2104
>
> On Tue, Sep 11, 2012 at 8:22 AM, Jim Thomson <jim.thom@telus.net> wrote:
>
> Date: Tue, 11 Sep 2012 10:26:27 +0200
> From: "Peter Frenning [OZ1PIF]" <peter@frenning.dk>
>
> Subject: Re: [Amps] MFJ products
>
>
> My 5 cents worth:
> I own and use several pieces of MFJ equipment, much of it has been in
> daily use for more than 10years:
> a MFJ-4245MV SMPS, no RF-hash, and has performed nearly 24/ 7 for
> more than 10years
> a MFJ-259B antenna analyzer, without a doubt the most useful tool
> in my toolbox
> I know there are better/more accurate/higher quality analyzers
> available now - at vastly higher prices!
> this one has been in use for more than 10 years in my shack and
> in the field, and when I broke it
> (my own fault - reverse polarity) MFJ was very helpful with
> repair suggestions
> I owned a MFJ-969 tuner for several years - did exactly what it was
> supposed to do at a very reasonable price
> Various power meters an dummy loads - again they have been
> performing exactly as expected.
>
> To conclude: yes corners have been cut here and there, but at the prices
> asked you get fair usefulness and many times equipment which few of us
> could afford without MFJ supplying it.
>
> --
> Vy 73 de OZ1PIF/5Q2M, Peter
>
> ## You obviously have not tried one of their SS HF linear amps..like the
> AL-600 or AL-1300. I defy anybody to get one to run full bore for 5
> years
> straight.
>
> Jim VE7RF.
>
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
--
Later,
John Bodine/WU2E
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|