[Bob]

Hello
This is my first try at restoration. I have a model 40-190. Got a schematic from Chuck S. I found that the 84 was replaced with an 80 tube. The power transformer was replaced also. The transfomer checks good ( on bench with no load ). The 61 cap was replaced with a 20mfd, the 60 resistor was replaced with a 500 ohm 2 watt and the 59 resistor is still a 15 ohm which got burned pretty bad. The 56 output trans (32-8053) secondary is open. The lead from the Feild coil 62 was tied to the filament of the 80 tube, this is a separate winding from theothe filaments. Neither lead of this winding is grounded.
My first ? is can an 80 tube replace a 84 without making some changes?
? 2 would this have caused the output trans to open?
? 3 is it possible to get a new power trans or rewind the old one?
? 4 is there a schematic that would show an 80 tube?
Finally ther are a some othe things that don't agree with the schematic would it be wise to make them agree?
Just want to say I already got a lot of great info from reading the other post.
Thanks in advance for any help.

Bob

[Bob]

Hello
Since I posted the above, I did some research, using a web site suggested by Ron R. It is a tube data/pin out site.
It looks to me like an 80 rectifier tube can be subsituted for an 84. The operating condictions and characteristics are very close to the same. It also showed a typical full-wave rectifier circuit, and it shows the field coil lead hook to the filiment. So I think I will use the caps and resistors called out on the schematic.
Anyone have a thought on this?
I would still need to replace the open winding output transformer. the Philco # is 32-8053, is there a sub for it.
Sorry about the first post, after I read it again it is a little confussing.
Thanks Bob

[Bob]

I was able to get another transformer. Please see new post "Philco Output Transformer". Need some help.
Thanks Bob

[exray]

The lead from the Feild coil 62 was tied to the filament of the 80 tube, this is a separate winding from theothe filaments. Neither lead of this winding is grounded.
My first ? is can an 80 tube replace a 84 without making some changes?

The most obvious difference between the two tubes is that the 80 has a 5 volt filament and the 84 is a 6.3 volt filament. Since you indicate that there are separate filament windings maybe that power transformer replacement was part of the "fix" since the stock xfmr in the schematic does not show a 5 volt secondary winding.
Its not an unreasonable repair although its hard to say which was the chicken and which was the egg. My thoughts are that the previous guy had to replace a defective power transformer with what he had on hand and that resulted in having to go to the 80 tube rather than vice-versa.

But who knows??? Since that type of change has been made it would be worthwhile to confirm all of the voltages and make sure they are still in the intended ballpark. I don't see any need to replace the power xfmr (your ? #3) if its working.

[Bob]

Hello exray
Thanks for the help. Your right I got the data sheets for the 80 & 84 and the filaments is the difference. The 80 tube also had a sample hook up, and the way my 80 tube was installed looks okay. I took the transformer out to shrink the leads and then powered it up. The filament leads for the 80 tube read 6 volts and the other one was 7 volts. This was no load so I think that would agree with what you said.
Thanks Bob