I just got my 46-1209 Philco radio console back from the repair shop. It worked well on AM, but there was nothing on SW. Is that normal today? I haven't used SW since the 70s, so I don't know if it is still active. I was really enjoying the sounds from this radio as I broadcast my own program from my ITunes via an AMT 3000. So after playing it for an hour Saturday night, I turned it off. In the morning I went to turn it on, and there was no power. I made sure there was power coming from the outlet. My repairman says he only replaces caps and resistors that are bad and leaves the rest, so I guess a cap or resistor could have suddenly failed. There was no smoke or anything. It's just dead. I know you can't troubleshoot it here, on the forum, but can anyone tell me who the major suspects are: transformer, speaker coil, resistor, etc and what percentage of the time they are the culprit? Thanks, Marc.
Can you tell if all the tubes are lit. Room may need to be dark to see those locktal
tubes. Shortwave should work too. Richard
Quote:My repairman says he only replaces caps and resistors that are bad and leaves the rest
There's your first problem.
If some of the paper caps were not replaced, they need to be. All of the electrolytics should have been automatically replaced.
But you say it has "no power" now? You mean total silence, tubes do not light up, pilot lamps on dial do not light up?
Did that repairman install a fuse? If so, it could have blown. The only other thing I can think of, if it is truly totally dead, is the power switch has stopped working. Or, a poor connection for the power cord was made under the chassis. In the case of the latter, this could be a very serious (and potentially lethal) problem.
My repairman answered me and he said he installed a 1.75 amp fuse. He said maybe it needs a bigger fuse. You were right on Ron! Thanks, Marc.
I don't think so, I think something caused that fuse to blow. At 1.75 amps, that fuse is a bit overkill for your set. Here's why:
At 115 volts, it was rated to consume 100 watts (1946 specifications from service manual).
I = P / E , where I = amps, P = power in watts, E = volts.
I = 100/115 = 0.87 amp.
Add a little more since today's line voltage is on the order of 125 volts in most areas, and your set probably draws close to 1 amp of current.
A 1-1/2 amp fuse should be plenty under normal conditions.
Make that repairman replace any paper and electrolytic caps that have not been replaced yet! Running an old radio with 65 year old capacitors is just asking for trouble. They WILL fail, sooner rather than later.
Yes, I think you are right! He or I should replace all those caps, not just the ones that aren't working. I'll do that and not put in a bigger fuse. Marc.
Hi Marc,
From your previous posts, it sounds like you would know how to replace capacitors yourself.
I would first do some checks, and see if the fuse was blown. Ron is right, something caused the fuse to blow. Installing a bigger fuse is dangerous, and could cause something to burn out elsewhere in the set.
Check the power switch to see if it is closing.
UNPLUG THE SET TO TEST.
Check the continuity of the power cord from the plug end, to the connection points inside the chassis.
http://www.nostalgiaair.org/PagesByModel...013586.pdf
If you look at the schematic, you can see the power plug wiring. Check to see if the phono light will come on with the power switch on, and the phono door open.
See the switches? If the main power switch doesn't get closed, no current will flow.
So concentrate on this section only for now. I would think that your 'repairman' would have checked and lubed the switches during the time at the shop. But I guess someone who only replaces parts as needed may not have checked the switch?
Sometimes a switch will get gummy, and the flipper inside does not make contact. A tiny shot of contact cleaner inside the switch will usually free it up.
Then the set should have been run for at least 3 hours or more on the bench as a test. If something went wrong, it would have failed at his shop. Hindsight is 20/20.
Let us know what you have found with the power cord and primary section. Still wondering what would cause the fuse to blow. Perhaps something in the phono motor? Hard to tell from here.
Good luck.
My repairman disagreed with the recommendation from Ron for a 1.5 amp. He said you need to compensate for the phono and lights. I took the radio back to him and he put in a 2 amp slo-blo fuse. It is working well now, but the push buttons don't work and I don't get anything on short-wave.
Take Ron's advice and have all the capacitors replaced. Your radio is a time bomb!
Steve
Thank you, Steve
I would not use one fuse to protect the radio and phono; I would either fuse the radio only, or fuse the radio and add a separate fuse for the phono if I wanted to protect everything with fuses. A 2 amp fuse will allow double the current to flow to the radio; if the phono is not on and something goes wrong inside the radio, the fuse may not blow until the power transformer cooks.
As Gary pointed out, installing a bigger fuse
is dangerous.
marcapra Wrote:My repairman disagreed with the recommendation from Ron for a 1.5 amp. He said you need to compensate for the phono and lights. I took the radio back to him and he put in a 2 amp slo-blo fuse. It is working well now, but the push buttons don't work and I don't get anything on short-wave.
If you want my opinion I think you should replace your repairman for two reasons:
(1) He can't read a schematic, the phonograph motor is operated directly from the power line, through the radio power switch, but is otherwise independent of the radio power supply. The factory wattage rating of the radio includes already includes the pilot lamps and usually the phono motor, so if anything Ron rated the fuse slightly too high, the fuse should be on the primary of the transformer not simply on the power line with the phonograph motor ahead of it.
(2) This is a 1946 Philco with parts that could be up to 65 years old, would you try driving a 1946 car with 1946 tires down the highway just because they hold air? Only a complete yo yo would perform anything short of a recap on a customer's radio of that age, caps are cheap as are resistors, and it takes just as long to track down the so called "bad capacitors" as it does just to replace them all, in reality they are all bad just some are worse then others, this is likely the reason that the short wave band does not work and the fuse blew. At the same time this set also has a power transformer and a filed coil on the speaker, those are not easy to replace nor are they cheap, a two amp slow blow fuse on the power line is more then large enough to allow the transformer to burn up should a capacitor short out.
Best Regards
Arran