voltage on tube heater 46-350
Posts: 24
Threads: 9
Joined: Feb 2013
City: Jasper Arkansas
newbie here got the old girl working by recapping and replaced rect tube am concerned about the voltage diff from the 40 till now should there be a problem with raising the voltage from 115 to 120? i figure it may be hard on filament heaters
Posts: 7,283
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Hi Mountain man and Welcome to the Phourm!
Wouldn't lose any sleep over the filament voltage. (Tubes with a cathode have a heater. Tubes without a cathode have a filament).Some of those 1.5v tubes have to run with 1.5v or a little better especially the 1R5. If you have any other questions you may want to start your own thread on the matter. It will be a little less confusing. Tnx for stopping by.
GL
Terry
Posts: 24
Threads: 9
Joined: Feb 2013
City: Jasper Arkansas
thanks for the info Terry it was just that the schematic shows 8.4 on tube heaters and at 123 vac this number is over that voltage considerably.
Posts: 24
Threads: 9
Joined: Feb 2013
City: Jasper Arkansas
Concerned about the higher operating voltages from 1946 110 to 2013 123vac in my area, this will raise heater voltages over 8.5 volts, I read that a power resistor may be in order, what type and size? also on alignment procedure it calls for an output meter to be attached to speaker terminals is this a volt meter?
Posts: 62
Threads: 8
Joined: Oct 2012
City: Hidden Valley, AZ
Resistors can be used to counter high line voltages, but either a bucking transformer or Variac mounted separately is a more efficient idea. Neither of them produces the heat as a resistor in the job would.
Any AC voltmeter with appropriate range can be used as an output meter, as you are just reading audio levels on the output, after using a tone modulated signal generator to accomplish set alignment.
Dennis
Pacing the cage...
Posts: 7,283
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
To add to Dennis's comments you probably want to use an analog meter just easier to read. It will be set on the low setting for AC volts.
A bucking transformers an easy way to knock down the line voltage.
GL
Terry
Posts: 4,686
Threads: 51
Joined: Sep 2008
City: Sandwick, BC, CA
I still say this 110 volt line voltage idea is a myth, unless you are dealing with DC power grids, most radios from then were calculated around a working voltage of 117 volts at least as the line voltages could very between 105 and 125 volts. If the line voltage is 123 volts that's still a little high but 6 volts high not 13 volts high. Bring it down to around 115-117 and it will be fine.
Regards
Arran
Posts: 24
Threads: 9
Joined: Feb 2013
City: Jasper Arkansas
does anyone have any information on component locations I see on the schematic "C"#'s. it would make alignment and part id a whole lot easier.
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Mountain man
Contact Chuck and get the entire package of service info for your set, it will save you some headaches.
http://www.philcorepairbench.com/schematics.htm
--
Ron Ramirez
Ferdinand IN
Posts: 24
Threads: 9
Joined: Feb 2013
City: Jasper Arkansas
Thanks Ron, also I am looking at a 20 ohm 25 watt power resistor to knock down the line voltage, any thoughts?
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Mountain man
As Dennis (Conelrad) and Terry (7estatdef) have mentioned, a bucking transformer or Variac would be a better way to reduce the line voltage if you are determined to do so.
Google the phrase "line voltage bucking transformer" and you should get several results on how to do this.
Also, please do not post about the same subject in different threads. This only results in confusion. I have merged one thread with posts on the same subject from another thread into this single new thread, to keep it all together.
--
Ron Ramirez
Ferdinand IN
Posts: 24
Threads: 9
Joined: Feb 2013
City: Jasper Arkansas
sorry just trying to get the hang it, please forgive my ignorance
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Don't sweat it, we're here to help.
--
Ron Ramirez
Ferdinand IN
Posts: 2,353
Threads: 92
Joined: May 2010
City: Clayton, NC
If you do use a resistor I would opt for something in the 40 watt range.
Posts: 2,128
Threads: 18
Joined: Oct 2008
City: Merrick, Long Island, NY
Yeah, would be nice to slim the voltage to filaments a bit with bucking transformer or resistor. Not going to lose much volume and might get another year or three from tubes.
Users browsing this thread: 1 Guest(s)
|
Recent Posts
|
Philco 38-2 Automatic Tuning
|
Hi Richard, I enjoy it to some extent. I do that type of work out in barn (modern) during the summer on nice days when I...dconant — 03:13 PM |
Philco 38-2 Automatic Tuning
|
hello dconant ,
my set is the tabletop one and it also needs refinished someone put plant or something on top and the f...radiorich — 02:56 PM |
Philco 38-2 Automatic Tuning
|
Well, you could take a look at most features of those radios, and other than some very few of them, they all are selling...morzh — 02:20 PM |
SABA 400 Automatic Stereo 11
|
I actually got to hear the SABA play today when I took my Westinghouse AM-FM up to be worked on and also now know a pric...Jayce — 02:08 PM |
Philco 38-2 Automatic Tuning
|
Seems more like a selling point to me. I too have have a Philco with the Cone-Centric tuning. Hopefully I will get the ...dconant — 12:17 PM |
Philco 38-2 Automatic Tuning
|
I found out, I never use it in my 37-116 and 38-690. I made sure it works, but this was it: I always hand tune.morzh — 10:55 AM |
Philco 38-2 Automatic Tuning
|
Does it wash your windows? Then it would be useful and worth fixing. Music and window washing.RodB — 10:00 AM |
Philco 38-2 Automatic Tuning
|
You press the lever (crank) and you rotate the dial into the desired position.
Also, while pressed, the contact that it...morzh — 09:50 AM |
Philco 91 Speaker Replacement
|
I do not have much experience with speakers, but acetone sounds right. It does not affect paper but does dissolve about ...morzh — 09:48 AM |
Philco 38-2 Automatic Tuning
|
Hello Dconant,
In my collection I have a model 38-7T which Philco called their famous "Cone-Centric" dial me...radiorich — 08:14 AM |
Who's Online
|
There are currently 1718 online users. [Complete List] » 1 Member(s) | 1717 Guest(s)
|
|
|
|