News:

"The phone is a remarkably complex, simple device,
and very rarely ever needs repairs, once you fix them." - Dan/Panther

Main Menu

Zenith H401 Radio buffs, help please..

Started by bwanna, September 08, 2010, 09:31:29 PM

Previous topic - Next topic

bwanna

thank you for the compliments & advice everyone...have no fear dennis, i will not hijack your repairman..  ;) the better half is a pretty handy tinkerer, i am sure with the schematics & advice he can get it working.

it will go up for sale in the antique store once it is fixed...i do love the design, but absolutley cannot start any more collections. we all know once you buy that first piece, you're doomed :o

briny, when i first started "saleing" i would never dicker on a price..but i soon learned  ;D i do hate when the seller will not name a price...if forced to make an offer, i will low ball big time. the people that come into the store with items for sale are sometimes offended that we won't pay antique stores prices to them. they don't understand they have put themselves in the posistion of being a wholesaler. as a dealer i am the retailer & have to buy low enough to make a profit.
donna

Bill

#16
The radio dates from 1952. The battery pack was a Zenith Z909 which, I believe contained both a 1.5 volt A-battery and a 90-volt B-battery. It was a big heavy rectangular thing, and quite expensive in the day. No longer made, of course, but there are nice repros.  You can see one in this video, though in a different radio.

http://www.youtube.com/watch?v=PjSAVbGHhkQ

If you want to operate yours on battery, you have two choices. You can build a "new" battery with an alkaline D-battery for the 1.5 V piece, and ten 9-volt transistor radio batteries snapped together for the 90-volt section. Cheap, easy, and small. You can do this yourself with some duct tape, or buy one of the nicely-packaged repros, as in the video above.

Or, you can buy a DC-DC converter for about $80. It holds a handful of D-batteries, and has an electronic circuit to convert it to the needed voltages.

Probably more than you wanted to know, right?

Bill

bwanna

thx for the info, bill. the radio in the video looks a fancier than mine. i probably won't fool with the battery, as it sounds expensive to replace. after it will work on ac power, too.

a friend found an original photo-fact sheet, from 1952, on ebay & got it for me. can't sell the radio now.. :)...hopefully can get it working. will let you all know when i do!
donna

Bill

Just as a quick FYI, info like schematics and PhotoFact sheets is available on line for free. When you need one, ask any radio guy.

Bill

KeithB

Donna, have you had any luck getting rid of that buzz yet?

Gary

#20
Just be careful working on this one.  First, I'm not an electronics expert but transformerless radios such as this one have a potential shock hazard.  These radios have one side of the line connected to ground with just a capacitor between the radio ground and the chassis.  The chassis may be hot when turned off or if the plug is reversed, hot when turned on.  If the cap shorts, and a person comes between earth ground and anything metal on the radio, they could receive a fatal, full line voltage shock.  Many recommend using an isolation transformer which electrically isolates the radio from an earth ground.

The rake symbol in the schematic is the floating ground or common return.  The ground symbol is the metal chassis.  Capacitors C9 and especially C17 between the two are the ones to note.  If shorted you can see how one side of the line is directly connected to the chassis.  These should be replaced with at the least 600V rated capacitors but better yet Y2 safety capacitors which, if they fails, will fail open instead of shorted.

bwanna

keith...too much going on right now for fiddling w/radios  >:(... gonna be a winter project. thx gary for the safety info.
donna

KeithB

Donna, that situation sounds all too familiar.  Good luck repairing it, and please do tell us how it sounds after it's fixed.   :)