Yaesu FT-101E tubes heaters question

[neazoi]

Hi this set was wired for 220v, which was the voltage my country had in the past. There is also a sticker (220v) at the back of the set.
Nowadays in Europe we use 230V. The set works on 230v ok but of course the heaters voltage and the output power goes up.
The heaters voltage is within limits (checked from the datasheet) but at the edge. The limit for the finals, from the datasheet, is 13.8v and my set has 13.69v. This is just about true for the driver tube.
Shall I worry about fast tubes deterioration or am I ok because the voltage is barely within limits?

I could rewire the set, but I like the extra output power, if it does not hurt. Bias is set correctly and monitored form the front panel meter to 60mA or less.

 

[danadakk]

Generally speaking component manufacturers over the years published
specs incorporated margin above and beyond the data sheet limits. So
what you described seems alright to me, especially as you have set the
plate current properly.

As far as incremental power out in Tx it really does not affect your "reach".

How do I increase range of ham radio?

Answer (1 of 7): My answer: Modulation type, frequency, antenna and then power. Range of radio is a science, not magic. So here’s some theory to back my points… Definition: S-Unit is 6dB. To increase the signal at the receiver by just one S-unit or one bar on a signal strength meter costs 6dB, o...

www.quora.com

Regards, Dana.

 

[Easy peasy]

the longevity will suffer - if that is acceptable, then no worries.

 

[neazoi]

the longevity will suffer - if that is acceptable, then no worries.

Even if I rewire the transformer for 228v, I see 13.5v in the heaters. This is just 200mV difference from 13.69v. The RF output power goes down by 15W or so. It depends on other voltages not just on the heaters.
As far as I remember, when I rewired the set for 230v (234v actually) the heater voltage did not got less than 13v.

 

[danadakk]

Here some comments from users -

Life span of a tube: How long?

How long is the useful Life span of a tube? Let's use some well known tubes in AR circles as examples, a pair of 6146 final PA tubes or some 4CX1500Bs...

forums.qrz.com

Regards, Dana.

--- Updated Sep 26, 2021 ---

Some interesting comments -

Vacuum power tubes, using old valves, and vacuum tube failures

Tutorial on vacuum tubes and how they work.

w8ji.com

Regards, Dana.

 

[Aussie Susan]

(Totally off topic - I used to lust over an FT101 when I started in Amateur Radio in the 70's. I'm amazed that they are still around.)
The most important thing in my mind is if you can get replacement vacuum tubes. If you can then I wouldn't worry about the 220V vs 230V. If you can't then I think you have larger problems than that - ultimately any valve will give up.
Susan VK3ANZ

 

[danadakk]

Converting finals to 6146 -

FT-101 6146B Conversion

Regards, Dana.