magnavox roundie

[timmy]

i was wondering about the one can cap on the tuner, are both connections coming off that can neg and the chassis positive? i know the one with the diodes is positive ground but the other im not sure. the other i put a cap and the votage there is 23volts but putting the cap in neg ground it only went to 22volts and clipping the cap the voltage in the cap drops instantly to 8 volts but turning the cap around useing positive ground the cap goes to 23volts and then clip it and it holds 23volts so i would assume this way is correct now. only because i dont have a schematic. thanks and ill get a pic of the table soon.

[timmy]

here is the turn table.

[tvtimeisfun]

Hello I have that turntable with the spindle and good needle and cartridge in like new condition will sell for forty bucks you pay shipping and cost of phono let me know.. Timothy

[timmy]

hey guys anyone know what to do with what looks like instant on, the tubes glow very little and the tuner bulb stays on alittle. how to do away with it since it causes problems and wear and tear on components and tubes.

[tvtimeisfun]

Hello some tube instant on has a switch on the tv on back to turns feature off, Magnavox tvs have that depending on the model of set you have.. Timothy

[Electronic M]

Usually there is a "vacation" switch to turn off instant on. Otherwise I'd suggest unplugging the set when not in use.

[holmesuser01]

Alot of tube TV's were killed by that 'instant-on' feature. I'd only use it sparingly.

Is there a MASTER switch on the control console?

[timmy]

i found no switch but then again i never leave any of my vintage sets plugged in. the only thing is a push pull switch next to the tuner that says auto- push and i have it pushed in thinking that will stop the instant on.

[holmesuser01]

That 'auto' switch might be for the automatic fine tuning.

[DaveWM]

look on the back for a sliding switch. if the tuner light is dim when the set is off then its in the instant on. there should be two sliders on the back (up high on the cabinet, not down on the chassis) one makes the image tint look less blue, the other is the instant on.

[Jeffhs]

Originally Posted by timmy

i found no switch but then again i never leave any of my vintage sets plugged in. the only thing is a push pull switch next to the tuner that says auto- push and i have it pushed in thinking that will stop the instant on.

One way to defeat the instant-on feature is to remove the diode across the TV power switch. This diode will be located on the back of the switch and connected directly in shunt with it. If it shorts due to, for example, lightning strikes, your TV will remain "on" permanently; the only way to shut it off will be to unplug the power cord from the AC outlet. Instant-on for televisions was popular in the 1970s, but later in the decade when energy conservation became the watchword in America, the feature was eliminated.

There could be a switch on the rear apron of the TV chassis to defeat the instant-on feature, if your set has it. If so, set the switch to "off" and the instant on feature will be disabled until or unless the switch is set to "on" again.

The previous poster could be correct as to the "auto" switch on your TV's control panel being the defeat switch for automatic fine tuning; in fact, if the switch is near the tuner, it may well be the AFT on/off control. I would try this: deliberately mistune the channel you use for your converter box or cable box output until you get colored "worms" on the screen, then pull out the switch near the tuner. If it is the AFT switch, the picture will clear immediately.

BTW, you are very wise not to leave your vintage TVs plugged in when they are not in use; even with the power switch set to "off", the power is not entirely disconnected from the set since most of these switches are single-pole single throw, meaning one side of the line will always be connected. Some AC/DC radios and televisions are even worse, as one side of the line is directly connected to the AC line -- meaning there is a 50/50 chance of inserting the line plug in the socket such that the chassis will be "hot" with the full line voltage.

Moreover, after 40 years or more (this is especially true of very old antique electronics), problems can and very often do develop, stemming from such things as leaky or dried-out capacitors (especially power supply filters), resistors drifting off value, and the like. Leaving a vintage TV or radio plugged in, even if it is not switched on, can be a potential fire hazard if a component should short and, for any reason, the fuse does not blow. Selenium rectifiers are particularly dangerous in this regard, especially very old ones; they can short without warning and release a gas that smells like rotten eggs. It is for this reason that it is recommended to replace old, obsolete selenium rectifiers with modern silicon diodes whenever possible. If you take this route, be sure to add a dropping resistor in series with the diode; this will ensure that the voltage at the output of the silicon will be equal to (or very close to) that of the original selenium stack.

[timmy]

by changing say the convergence selenium stack, i dont have the schematic to get an idea what the voltage is at that rectifier or what resistor to use, i think it would take 3 diodes to replace that selenium. others have told me dont bother with the dropping resistors because its not much difference in voltage and the fact that these old sets have a built in 20%-30% tolarance already.

[holmesuser01]

I'd get the thing running before you think about changing out stuff like this.

[timmy]

well guys your right the instant on switch was on the back as i looked at the back cover and it says quick picture so that will be switched off. all thats left is tv chassis caps and found one 100 ohm resistor bad in the convergence board. the turn table was missing the needle cartridge but i had one to put in. just waiting for the caps and then its a go to the finish and see just how good a picture it produces. and for all you guys that told me my hv probe was lying to me, well i got another now.

[timmy]

here is an update on old maggie.