6146Ws in Heathkit Apache

[w5gw]

Has anyone tried these and what has been success?

tnx Gary

[K1DEU]

 6146W's  Only more testing after production. Does not make a different valve. Mostly GE's were the good reliable ones.

[KZ5A]

Gary,

I'm in the process of re-building a Viking 2 and am going to run 6146W's of the later "6146B" type.  I expect them to work fine... but only time and finishing the project will tell.

I attached a document I ran across that explains the family tree for the 6146' A, B's, and W's.

73 Jack KZ5A

[KZ5A]

Here's another that didn't get attached

[WA5VGO]

I've said this many times. I've NEVER had a radio they didn't work in. And this covers a lot of radios (including the Apache). I think there is a lot of misinformation out there about 6146B's and 6146W's.

Darrell, WA5VGO

[W2VW]

I've said this many times. I've NEVER had a radio they didn't work in. And this covers a lot of radios (including the Apache). I think there is a lot of misinformation out there about 6146B's and 6146W's.

Darrell, WA5VGO

And 813s and 3-500Zs........

[W7TFO]

A 6146 in any clothing is not on the same plane of reliability as the 813. 

Not to say they don't work properly, but I feel the range of application is limited. 

If one keeps the throughput akin to it's grandpappy, the 6L6/807 you will be happy.

Harken back to the early Ampeg SVT that used 6 of them in PPP.  legendary flames happened.

73DG

ps...not that the later 6550 was a good idea in that amp either.

[WQ9E]

I've said this many times. I've NEVER had a radio they didn't work in. And this covers a lot of radios (including the Apache). I think there is a lot of misinformation out there about 6146B's and 6146W's.

Darrell, WA5VGO

My experience mirrors that of Darrell.  I have used 6146W tubes in various Johnson rigs, Heathkit SB and HW series, Kenwood, etc. 

A couple of caveats:  There is supposed to be a problem with the neutralization circuit in early Collins S line (and KWM-2) gear that would also create a problem with using 6146B tubes, slight changes were made in later production.  There was also a bad production lot of GE 6146W tubes that made it into circulation.  They either were not degassed properly in production or there was a problem with materials or seals.  A couple of friends bought some of this lot from Fair back in the 90's (which Fair quickly replaced).  There are probably some of these problematic W production lot still out there which may be feeding some of the internet rumors about W tubes not working in some gear.  These bad tubes light up like a VR tube as soon as HV is applied.

I would not hesitate to use 6146W tubes in the Apache.  A bigger Apache concern is make sure you carefully read the manual section on audio setup to avoid a mistake.  The control hidden behind the CW key jack is most important in proper audio setup.

[W3SLK]

I'd be more concerned about using 6146B's than I would W's. The way I understand it, the W's are closer to 6146's /A's.

[WQ9E]

W suffix were available over a period of time and some of them are based upon the original 25 watt Pd design while later ones (the majority that I have seen) have the larger plate structure of the B variant.

If you look at the original specification sheet for the 6146B from RCA they state unequivocally that the 6146B is unilaterally exchangeable with the 6146, 6146A, and 8298.  The later production W variant has the same internal capacitance as the B suffix 6146. 

I have never heard any credible reports of problems other than with some of the earlier Collins gear so I would interpret that problem to be circuit design rather than tube design.  Collins marketing could describe the neutralizing circuit as having been perfectly and specifically designed for 6146 tubes while an outsider might observe that the original configuration was not very robust against very minor differences in tube characteristics. 

[W4AAB]

6146W's were the ONLY variant of 6146 that stayed stable without oscillating in my Swan 250 6m rig I used to have. The main thing with the Apache is get rid of those 510 pF coupling caps and put in .05 uF.