[R-390] Sigmapert 26Z5W's and otherness

[sigmapert]

Hi Ken,

when handled appropriate solid state devices are not fragile. But if you e.g.
would remove or insert the CPU in a running computer you certainly wouldn't be
surprised when the CPU thereafter is scrap.

Each of my 3TF7 replacements is accompanied by a brochure. Point 1 of the
therein contained replacement procedure states: 'Switch the receiver OFF'.

Using a LM 317 in current mode or a 7812 voltage regulator produces considerable
heat requiring a bulky heat-sink. No chance to construct a true plug-in device.

One remark regarding the use of modern components in vintage gear. IMOH
acceptance depends on at least 3 criteria:

1) the technical data have to be BETTER than the original ones

2) the modification has to be fully reversible

3) the replacement should optically nicely fit into the vintage gear

Best Regards & vy 73

Kurt - DH3PJ

mailto:sigmapert at r-390a.eu


am Freitag, 20. September 2013 um 23:30 schrieben Sie:

> Good morning List,

> I just had a look  for the 26Z5W replacements and they are all sold already. Hopefully he'll have some more soon.

> Currently I have his C603 and C606 capacitor replacements in two of my radios
> and will shortly get another set for my other radio. They are indeed nicely made. Very elegant indeed...

> Until a few nights ago I had one of his 3TF7 replacements which was working
> well...until I made the mistake of switching back to the original glass 3TF7
> with the receiver powered on. You all are probably wondering why I even
> thought of it...I was trying to track down a noise issue so I did a quick A/B
> test. Now the unit is non-functional so I'm back using the glass 3TF7. So
> please learn from my mistake! The replacement 3TF7 seems to be electrically
> fragile in that regard. BTW no...that is NOT a criticism, just an observation.
> I built a SS regulator for the 3TF7 some time ago using an LM-317 and that
> thing is very robust so I'm probably going to go back to using that.

> Kind regards,
> Ken
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