Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Were There Different Runs Of The 40-190?
#4

Pepperoni Wrote:Thanks Glenn! I've got all the NA Riders paperwork and my own original Beitman schematics. All showing the 7J7. I know the 5Y3 isn't correct and why it was changed I don't know. 84 has a 5 pin socket and it was changes to a standard octal to support the 5Y3. Okay to run the 5Y3 but not with an aftermarket power transformer that's rated 250-0-250 on the hi-voltage outputs. If my memory serves me well the 5Y3 wants plate voltage of 350-0-350 for the hi-voltage. The transformer that's on it now has a big puddle of wax under it so I know it got very hot. Haven't checked winding resistance yet. Puddle of wax could have been from the original transformer. Just gettin' started on it and wanted to figure out this 7J7 issue 1st. A couple of resistors coming off of the 6J8 are color coded grn. stripe with brown body but they don't read anything with a "5" at the beginning. In fact they both read completely different by hundreds of ohms.

I'll get in touch with Chuck. His paperwork is always great.

Thanks again,
Pepper

A 5Y3 doesn't care whether it has 250 volts on the plates or 350 volts on each plate the only thing that matters is what the current load is on the output of the tube, in the case of a 5Y3,5Y5, and an 80 the maximum current is 125 milliamps. Quite clearly the original transformer packed it in and someone could not find, or could not bother to find a duplicate of the original. If the original was a type 84 the filament voltage is 6.3 volts and is normally powered from same filament winding as the rest of the tubes, unlike the 84 the 5Y3 does not have an indirectly heated cathode so it needs it's own 5 volt filament winding. The filament current of a 5Y3 is 1.5 amps, which is pretty standard, so if the new transformer has a 5 volt winding it should be able to take that tube. If the transformer is running hot it may be that either the high volatge winding or the 6.3 volt filament winding cannot handle the current load of an eight tube set with push pull type 41s.
Regards
Arran


Messages In This Thread
Re: Were There Different Runs Of The 40-190? - by Arran - 09-24-2011, 02:13 AM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco model 60
Yes I was there. I got some real bargains there. Plus a Zenith 7G605 clipper that I have been trying to find for a fair ...Radios1340 — 01:46 PM
The speaker table error?
G  10-1/2"       65, 76, 87, 95 Push-Pull 45's 2766 0.7 550 3200 H   10-1/2"    77, 96 Push-Pull...morzh — 09:26 PM
A Marconi model 86
I have a Stromberg, one of the early ones, seems early 30s. This is what I call a back breaker. None of the early Philc...morzh — 08:28 PM
A Marconi model 86
A backbreaker.....PaulPaul Philco322 — 08:12 PM
A Marconi model 86
>>What a behemoth! A Juggernaut.morzh — 07:47 PM
Philco 70 antenna lead
I am not sure I understood about the coils and the mush. I looked an more than one coil in 20, 70, 90, 60, Zeniths and ...morzh — 07:46 PM
A Marconi model 86
:e_biggrin: What a behemoth!  I hope the final result is as much a quality sounding example!  Keep us posted on your pro...GarySP — 07:32 PM
A Marconi model 86
I should add that the double conversion may only be used on the shortwave bands, but I haven't looked at the schematic t...Arran — 07:27 PM
Philco 70 antenna lead
Yes, that wire will not pick up much interference as routed - the RF at that level won't be affected, and if you have st...radio1 — 07:26 PM
Philco model 60
I'm also a member of MARC. Did you attend the Vintage Electronics Expo in Waterford, MI last month? That's where I got...GarySP — 07:22 PM

[-]
Who's Online
There are currently 6623 online users. [Complete List]
» 2 Member(s) | 6621 Guest(s)
AvatarAvatar

>