[TenTec] Fragile Radios

[Joe Roberts]

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