I have a really nice Omni V and have never been able to make much use of
the audio filter in the rig. Instead, I use a Autek external filter to
good effect. Does anyone here know if this could be a problem with
older electrolytic caps? Since I plan to use this rig for many more
years, would it be advisable to recap it like Joe has suggested? I also
have done this many times with my older boatanchor radios.
Steve WA9JML
Joe Roberts wrote:
> On a related note, I wonder whether early digital gear like Omni V ages
> so well. Specifically, wondering about the electrolytic capacitors.
>
> Case in point: Picked up an Omni V and the potential was there but I
> found it to be a rather hissy and spitty set. NOT pleasurable to listen
> to. Too much high frequency garbage. Made my ears hurt.
>
> Contrary to the "If it ain't broke" law, I decided to replace a few
> strategic caps on the logic board with super low ESR motherboard caps
> like Rubycon MCZ and Sanyo Oscon. Wow, spurious noise level went way down.
>
> Emboldened by this result, I recapped the entire IF/AF board with
> similar quality caps. WOW WOW WOW. The V is now super quiet and real
> well behaved. The difference is NIGHT and DAY.
>
> Two questions:
>
> 1) Were really good electrolytic decoupling caps for digital available
> in 1989?
>
> 2) Are the yellow IC caps Ten Tec used even on the same planet
> quality-wise as 2007 low ESR, HF rated caps.
>
> I think not. I figure Ten Tec used good quality, but not exceptional,
> 1989 commercial grade parts....and these are getting rather long in the
> tooth to boot.
>
> A rig like the Omni V is digital and needs good caps and the ones in the
> radio were probably not the greatest then and certainly aren't now. My
> theory is that the marginal decoupling capacitors are part of the blame
> for some of the noisy rigs out there.
>
> Reminds me a lot of recapping old boatanchor radios, which I did a lot
> of. Yanking out some funky wax caps and putting in Orange Drop 715Ps
> really brought these old radios to life.
>
> Time files...maybe we should start thinking about some of the 80s rigs
> in the same light. My experience is that putting new, fresh, & really
> fancy capacitors in the Omni V vastly improved the radio, and I only hit
> a few of the high spots with the replacements. Will probably do the
> whole radio over time.
>
> I can now say that if an Omni V is at all noisy, it is not working right.
>
> When I was messing with vintage tube radios, I struggled with the idea
> of keeping them original, but for radios I wanted to use, I usually
> went ahead and recapped because the performance gains were so high.
>
> I am following the same logic here with, so far, very positive results.
>
> Joe N5KAT
>
>
>
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>
>
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