Interesting.
I got the TT 963 supply with my Orion. I was surprised the first time its
fan turned on. Just sitting on the desk with the Orion in RCV, the fan will
run once in a while.
----- Original Message -----
From: "Mike Coogan W7MGC" <mikegc@pacifier.com>
To: <tentec@contesting.com>
Sent: Friday, July 15, 2005 18:09
Subject: [TenTec] Fw: Cooling fans and IF gain
> I noticed the same heat build up on the 962 p.s. for my Omni 6+ when
> running Rtty. I mounted a TT 310 fan on the heat sink of the power
> supply, powered from the 12v dc outlet on the p.s.
>
> Mike W7MGC
> Vancouver, Washington
>
> Omni 6+ >>253 Auto Tuner>>HercII amp, Love it!
>
>
> ----- Original Message -----
> From: "Robert & Linda McGraw K4TAX" <RMcGraw@Blomand.Net>
> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> Sent: Friday, July 15, 2005 6:08 AM
> Subject: Re: [TenTec] Cooling fans and IF gain
>
>
> > Interestingly enough, the Omni VI+ PA is rated at 100% duty cycle
> > while the
> > 961 power supply is not. I've found that additional cooling on the
> > power
> > supply is necessary in high duty cycle modes, partly caused by the
> > bridge
> > rectifier being mounted to the bottom plate for heat dissipation. A
> > small
> > 12V fan blowing on the heat sink in the rear takes care of the
> > problem.
> > Also, one might take note that if the power supply is sitting flat on
> > the
> > desk there is little room at the bottom rear for vertical air
> > convection.
> > If possible, elevate the power supply, allow the heat sink to hang off
> > of
> > the rear support and allow the heat sink to have more "breathing
> > room".
> >
> > As to the Omni VI+, I've found that heat build up within the radio
> > does
> > cause some frequency drift primarily due to BFO frequency changes. I
> > changed my BFO's to TXCO's and found a nice improvement. All in all,
> > probably not worth the investment, time and effort, for such a small
> > benefit.
> >
> > I've read cases where one removed the speaker, replaced it with a
> > computer
> > type 12 V fan that made improvements of about the same magnitude to
> > the
> > radio. This would be a lot less work and a lot less $$.
> >
> > 73
> > Bob, K4TAX
> >
> >
> > ----- Original Message -----
> > From: "Chuck Guenther" <ni0c@earthlink.net>
> > To: <tentec@contesting.com>
> > Sent: Thursday, July 14, 2005 8:17 PM
> > Subject: [TenTec] Cooling fans and IF gain
> >
> >
> >> N6KB wrote: "I find that operating my Omni VI in CW contests a fan on
> >> the
> >> PA heat
> >> sink is necessary. My Kenwood TS-440 has a built-in fan with
> >> temperature
> >> controlled speed, or at least duty cycle. The TS-440 receiver
> >> performance in contest conditions does not compare to the Omni VI
> >> though. I wish Ten-Tec would have included a built in fan. I have
> >> never
> >> tried, or thought that I needed, a fan to ventilate the insides of
> >> the
> >> Omni VI though."
> >>
> >> I used a TS-440S for about seven years (in fact I still have it).
> >> The
> >> only time the cooling fan ever came on was during an RTTY contest (I
> >> was
> >> running about 60 watts). It never came on when operating CW or SSB.
> >>
> >> With the Ten Tec rig, I find the heat sink of my 961 PS always runs
> >> at a
> >> higher temperature than the Omni 6 PA heat sink.
> >>
> >> Today, in order to alleviate my gain problem, I swapped out the Ten
> >> Tec
> >> 221 filter for the INRAD 753 (which has a few dB less insertion
> >> loss).
> >> The gain seems adequate (and more stable) now, so perhaps my problem
> >> was
> >> in the filter, or the connections thereto.
> >>
> >> 73,
> >> Chuck NI0C
> >> .
> >> _______________________________________________
> >> TenTec mailing list
> >> TenTec@contesting.com
> >> http://lists.contesting.com/mailman/listinfo/tentec
> >>
> >
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|