[TenTec] Fragile Radios

[Steve Berg]

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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