SP600 LED light replacements.. NOW this is odd!

[ke7trp]

I said before..  It was the act of myself installing the bulbs or the LED bulbs themselves.   

I love it.  To lazy to get the manual out to help. But not lazy enough to type that big negative post up.

Jim. I bet you might be right. Let me try to isolate those sockets and check for shorts.. The wire goes IN and back OUT of the socket in a daisy chain.

C

[N3DRB The Derb]

I think Jim's theorem is pretty logical. check it out. On some philco BCL sets there are pilot lamp holders that will take out the set's power transformer if they are not spotted before you flip the big switch. they short right to chassis ground after 60 years.

Vitamin Q oil caps were damn good caps but I have seen plenty of leakers and it's just bad form to trust caps to be ok after 50+ years of usage.

[WB6NVH]

I wasn't really too lazy, I did find the manual after that - - when you have five full size file cabinets full of manuals, out in storage, at night, it gets hard to find stuff!  

The lamps just go in parallel and are on their own winding off the filament transformer with one side grounded, at least on the JX-26 series.

I'm sorry if you thought my post was negative, I didn't intend it that way.  If you take offense easily at anything anyone comments about a technical problem, then you'll probably find that possible help becomes scarce after that.

[KB2WIG]

When I have problems, I sometimes use this.

[W6TJK]

Clark,
another thing to consider is that the LED's likely pull a LOT less current than the #49's.
if so, mebbe the fil's got juiced up a bit and that led to a bit more current flowing in various places, pushing marginal parts over the edge.

but, your comment about possibly a physical tweak when you replaced them may be ...

Hey, we gotta QSO on AM some night.

I got the 500 up and flaring !

t

[N2DTS]

The new LED xmas lights have diodes in line, and run in series, and they can and do short out.

If the LED lights you put in still work ok, they are not likely to be the source of the problem, the only thing you would see is much less current drain per bulb, but on a filiment line, that would be a VERY small change.

Most LED's have dropping resistors in them to limit the voltage/current...

Brett

[ke7trp]

TJK. Nice to see you on here man. I heard you several times on the 500..  So happy you got off that weak Rice box!  I am sure with your 500 we will be able to talk more.  I just picked up a T368 so I am sure you can hear me now too!

Clark

[ke7trp]

I put one in the NC300 tonight. Nice and bright.  Been on for hours. I dont think this was my issue. I think it was time for the caps to just go. 

The NC300 is ok.. But does not even come close to the SP600 in audio and clarity. 

Clark

[ke7trp]

SP600 is fixed.  Bad caps.  Why they decided to go the exact moment I put the LEDs in is the question.  But they did. The Caps in the PS and the caps in the audio section where all bad.

I cant wait to get this Radio up and running. The NC300 is a nice old reciever but it does not even come close to my old Friend, the JX14.

I got an original Wrinkle black SP600 case for it.  When I get back into town, I am going to install it and put it back in service with the T3



C

[flintstone mop]

Glad you found the problem.What a crazy coincidence that there were other failures.
The LED's did not cause the problem.

Fred

[ke7trp]

You dont know that Fred.  I would not put these LEDs in an Sp600.  You might have the same problem


Clark

[Gito]

Hi

One reason that caused A cap go bad is over voltage input,
when  You changed the #47 bulbs with LEDs, the load presented by this four #47 gone and since led is actually a "diode" with small current flowing in it,also a half wave rectifier,it  doesn't load  like the #47 bulb.
The transformer is more lightly loaded.

Because LEDs conducts only on  half cycle,it loads only at that cycle .when the other cycle arrived (LED is not conducting), the load at the Transformer is gone.(supply winding for the Bulbs)
So as a whole the transformer gives a higher voltage at that time.(since it's more ligtly loaded
it includes also the HV supply.

because You wrote You get get a higher volume.... and so on after using leds,it can only be caused by higher HV voltage,that in turns blows the Capacitors
Just a though.

Gito

[ke7trp]

I believe that you are Correct Gito.  I would not put these into radios that use multiples.  The old Components cannot take the increased voltage.

Clark

[WD5JKO]

I believe that you are Correct Gito.  I would not put these into radios that use multiples.  The old Components cannot take the increased voltage.

Clark

Clark,

    So are you ready for another trial run with those LED's in that SP-600? 

BTW, with my SP-600 I solid stated the HV rectifier (5R4). After doing that I changed the C-L-C pi filter a choke input type. I doubled up the capacitance after the choke. The final B+ was lower than stock, about 220v as I recall. If your willing to part with those LED's (I'll pay you), then I can try them on my SP-600.

Jim
WD5JKO

[WBear2GCR]

some of the LED replacement bulbs have driver ICs in them, this keeps the LED current constant and the light output even with varying input voltage...

                        _-_-bear

[ke7trp]

Damn.. Got the Sp600 back up and running in the case with the T3.  Now the CW switch is toast. I can hear a relay click but the BFO wont engage. So I cant zero beat anyone.  Time to yank it back apart!

C

[W3RSW]

The old girl's trying to tell you something. 

[ke7trp]

Yeah.. That she is real pissed I put modern LED light bulbs in the sockets.

C

[ke7trp]

This mystery is now solved.  I got the new ER today in the mail. There is article explaining why NOT to put these in old radios. It seems you get the 1.4 X voltage increase. With FOUR of them wired the way they are in the 600, This was NOT good.

C