Posts: 10
Threads: 3
Joined: Nov 2018
City: Wayne
State, Province, Country: NJ
The original power cord on my Model 51 radio was replaced a long time ago. If I were to replace it again, should it be replaced with a three wire cord so that the grounding wire would not be a separate wire, but part of the power cord?
Thanks.
John
Posts: 7,283
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Personally I like separate grounds (chassis not connected to the outlet ground)as they can be noisy. Use a reproduction cloth cord.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 691
Threads: 8
Joined: Apr 2018
City: S. Dartmouth
State, Province, Country: MA
I don't add chassis grounds via the power cord either. Same reason, ground to the panel will likely travel some distance with all the noises of the AC line.
Chas
Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
Posts: 10
Threads: 3
Joined: Nov 2018
City: Wayne
State, Province, Country: NJ
Thanks very much. I appreciate the advice.
John
Posts: 619
Threads: 42
Joined: Mar 2017
City: Gap Mills Wv 24941
to be slick, use a power cord that has a fuse built into the plug.
has a little slide door to which you can remove and replace the fuse.
Posts: 23
Threads: 2
Joined: Dec 2018
City: New York
State, Province, Country: New York
Nice idea for the fuse, where can I get such a plug?
And for obsessive-compulsive purposes only, what color was the original cloth-covered power cord? Brown, brown-yellow?
And how long?
My "find" (16b Cathedral) only has the stub of a cord, so if I'm going to restore, might as well do it right.
Posts: 619
Threads: 42
Joined: Mar 2017
City: Gap Mills Wv 24941
i have a cord from another item from the past.
the easy place to find the plug i speak of is on christmas lights.
i am sure i would be able to find the plug cord from another item but i am betting i wont like the price.
so... i am doing a quick study on the christmas light plug.
so far i am not impressed because the christmas light plugs are not polarized,,, but the christmas light plug has TWO fuses!
this option is going to be very very very inexpensive to integrate into radios.
this is like the one i harvested from something else,, i think it was from an old box fan??
http://www.nbwell.com/products_detail.as...779&page=1
these are very nice, not so expensive but the darn thing has no onboard fuse....
https://www.oogalights.com/Leviton-Black...E#features
i cant tell if this darn thing has the fuse or not
https://www.1000bulbs.com/product/172795...etail-tabs
then there is this what the industry calls "VAMPIRE ZIP CORD PLUGS " which has a fuse provision and its 90deg style so to speak...but ... i dont like the idea of insulation penetration dependent cords ... but... it might be good nuff for what we do?? pack of 12 for cheap
https://www.actionlighting.com/spt-1-spt...ugf-white/
tractor supply has a bakalite rendition of the old USA old radio plug that has a onboard fuse,, looks like NOS usa stuff from yesteryear but made in china.
Posts: 751
Threads: 91
Joined: Nov 2015
City: Jonesboro
State, Province, Country: AR
I buy a variety of the round vintage style reproduction plugs here. They have the Acorn, faceted, MCM and "Deco" styles. I usually get black or brown.
https://vintagewireandsupply.com/plugs-connectors/
For cord, I get brown 25' and cut to 6'3", so I get 4 cords from a roll.
http://www.radiodaze.com/brown-braid-clo...em-pwc-1a/
Blessings,
Jeff W.
Jonesboro, Arkansas
http://jeffsradios.weebly.com
God loves you as you are, not as you should be, because none of us are as we should be. - Brennan Manning
Posts: 23
Threads: 2
Joined: Dec 2018
City: New York
State, Province, Country: New York
The original power cord on my 16b is missing the plug, but is otherwise 8 feet, 2 inches long. Brown, cloth-covered, hard wired to the chassis (i.e., no cheater plug).
I am making the replacement 8' 6" but still mulling the idea of a fuse somewhere externally on the chassis (for safety reasons).
The original cord was black and black-with-white-tracer.
Which is the neutral? From the schematic, it would appear to be the black-with-white-tracer and that the hot line is routed through the shielded cable (clever, that) to the on-off switch. True?
And, what did the original plugs look like?
Matthew W. Woodruff
Posts: 751
Threads: 91
Joined: Nov 2015
City: Jonesboro
State, Province, Country: AR
I've always been told to connect the hot lead to the switch side.
Philco used a variety of the round plugs, similar to the link I provided in my earlier comment. I have a 16B here with a brown faceted Bakelite plug like this:
https://vintagewireandsupply.com/antique...ark-brown/
Blessings,
Jeff W.
Jonesboro, Arkansas
http://jeffsradios.weebly.com
God loves you as you are, not as you should be, because none of us are as we should be. - Brennan Manning
Posts: 1,186
Threads: 49
Joined: Oct 2017
City: Allendale, MI
I have a few Elmenco fused plugs. Are these at least similar to what were used back in the day? Made in the USA.
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
37-116, 37-690, 38-116, and 38-690 used those Elmenco plugs.
--
Ron Ramirez
Ferdinand IN
Posts: 1,186
Threads: 49
Joined: Oct 2017
City: Allendale, MI
I'll start using these instead of putting a fuse holder under the chassis. I've got 20 of them!
Posts: 10
Threads: 3
Joined: Nov 2018
City: Wayne
State, Province, Country: NJ
What amp rating is recommended for fuse?
Posts: 619
Threads: 42
Joined: Mar 2017
City: Gap Mills Wv 24941
JRC0109,,
you have to design your answer around your print or device you are working on
your prints normally will tell you in a round about way what amps the unit uses at nominal working conditions.
breakers are sized with the max normal working condition times 1.20.. ie- 10A nominal so 10x1.2 = 12A,, so next reasonable size "UP" is used.
fuses on the other hand are not so easy to calibrate during manufacturing cause its just normally a thin metal strip,, so the industry applies the rule multiplier of 1.5. ie- 10A x 1.5= 15A, so use a 15A.
in radios which i am new to here, ive noticed the prints say a couple things like your volts and your watts.
the formula is power = current x voltage,, so to solve for current, you do........
power divided by voltage = fuse size in amps but remember this is at nominal working conditions.
when the radio is coming up on line, the amps used during that warm up time frame of maybe as high as 10 seconds might reach 160% of the amps you calculate due to what i personally call inrush.... (think motor load coming up to speed but not exactly a good example here as motor loads 30amps in the first 15u/sec can be nearly 200Amps! circuit breakers can be made t absorb and work "with" inrush. ). Fuses cant be made as easily as breakers when it comes to a calibrated amount of amps which the over current protection device will "open". Fuses are treated way different from breakers. Fuses that can work with inrush are usually called "slow blow" and visually have more than just an element within the sight glass.
your line voltage is higher today than what your print may say.. which most say 115vac or 117vac.
if your radio says 150 watts and it says 117vac,, then the math says at that time 1.3amps would be the expected draw.
since you plan a fuse in your circuit,, 1.2 x 1.5 = 1.8amp fuse required,, which means you would use a 2amp fuse.
watts never really changes , its like a constant or the "result of resistance, voltage and current,, what did change for your radio is the voltage. Lets use the 150watt example again but use todays voltage on our outlets.
150watts divided by 124.2vac = 1.207 amps,, and x 1.5 multiplier for a fuse you are at 1.81 amps. you should size to a 2amp fuse here again but.. you may make a choice to use a 1.5amp.
in my Zenith 7h960,, the print says 50watts and my outlets are about 124vac so that means my fuse i pick is really close to 1/2amp.
i installed 3/4A.
all the details above were to benefit anyone who wanted to know how to size the OCP under any normal condition on any device, sorry for the long answer.
(This post was last modified: 01-01-2019, 10:54 AM by jcassity.)
Users browsing this thread:
|
Recent Posts
|
Jackson 715 not working
|
Mrfixr55, its working now. I cleaned the switches and sockets with spray cleaner. Thanks for helping on this one.daveone23 — 06:26 PM |
Jackson 715 not working
|
Now that you posted the schematic, I don't know why that Sprague electrolytic cap is across the meter, as it is not indi...MrFixr55 — 05:51 PM |
HiFi (Chifi) tube amp build - but my own design.
|
What may be lacking in the PP Tube amps may be the 2nd harmonics, which some, especially RCA back in the day called &quo...MrFixr55 — 05:32 PM |
Jackson 715 not working
|
Usually in an emission tester, the tube under test is measured as if it were a diode. So, some testers connect all the g...RodB — 04:17 PM |
Restoring Philco 37-604C
|
Yep. F5 is green, D5 is Red.
Red is Bad.
Green is Clean.morzh — 01:30 PM |
Jackson 715 not working
|
I did start to do that but I stalled out because I could not figure out how the grid and plate get voltage. In this diag...daveone23 — 11:52 AM |
Restoring Philco 37-604C
|
(Insert Homer Simpson "DOPF" Here.)
When all fails, look at the can. Took the Ron Ramirez advice, red Caig D...MrFixr55 — 09:23 AM |
Philco 91 Speaker Replacement
|
From your text I am not sure if you intend to use the existing speaker with a resistor instead of the field coil.
It wo...morzh — 08:44 AM |
Philco 91 Speaker Replacement
|
My field coil is bad. I am still hoping to find an original, but if I can't I will go with a fitting Philco speaker, 125...dconant — 08:34 AM |
Philco 91 Speaker Replacement
|
As Rod said, it is OK to use a fitting speaker, and then look for an original one.
If you buy a Hammond 125 output tr...morzh — 08:15 AM |
Who's Online
|
There are currently 5305 online users. [Complete List] » 2 Member(s) | 5303 Guest(s)
|
|
|
|