[Hallicrafters] Tubes, is it my imagination, Or?

[Phil Atchley]

Hello all
Over the years (since mid 50s) I've worked on a LOT of old radios.  In my
younger days, I always thought "newer was better" 8^)  In other words, I
always thought the newer sets with all those cute little 7 and 9 pin
minature tubes HAD to be better than the large old octals etc.

However, in the past two years I've done several sets with the older, larger
octal tubes.  3 were Minerva Tropic Masters, one Hallicrafters SX-110 and a
Hallicrafters 5R10A.  In the two Hallicrafters sets, "most" of the tubes
were original Hallicrafters tubes.  (The 5R10A rectifier had been replaced
and in the SX-110 the rectifier and one other tube changed)  In the Minervas
I believe many of the tubes were original, though, those sets being wartime
units it is hard to tell as they had a variety of tubes.   I did have to
change a couple tubes in the Minervas myself.

BUT, this brings up an interesting question.  DO the old Octal tubes
actually have a longer lifespan than the minatures do?  Except for guitar
amps where they take a beating it seems I have run across "few" microphonic
ones and they just seem to give fewer problems overall.  It also seems like
the filaments "flare up at turn-on" less than the minatures do.  Perhaps
that is part of the key along with wider element spacing.

OR, is it my imagination playing games?

73 de Phil  KO6BB
Loving home provided for wayward Boatanchor Receivers
ko6bb at elite.net
Merced, Central California
37.18N 120.29W CM97sh



---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.325 / Virus Database: 182 - Release Date: 2/19/02