Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Mike Osc AM radio transmitter?
#14

(02-23-2018, 07:37 PM)TV MAN Wrote:   BTW, are you the same 35Z5 from ARF?

One in the same.

If only using one primary winding the available current on secondary is going to be half, less what's drawn by the primary now supplying B+ voltage... BUT the tubes draw such a small amount of current it's a non-issue... The secondary is center tapped so you'd only need half, rectify & filtering that 3v would give approx 4.2v DC... Will only require a small amount of resistance added... You could start out on variac, then increase voltage to see what input is necessary to give proper filament voltage... Rather than risk tubes, use something like a #47 dial bulb for load... Also possible to use resistor in primary circuit of transformer, that would limit B+ & filament voltage... 

I may seem cautious but those frail little battery tubes give me the willies... I stay away from them as much as possible...


Messages In This Thread
Mike Osc AM radio transmitter? - by TV MAN - 01-29-2018, 05:57 PM
RE: Mike Osc AM radio transmitter? - by Arran - 01-30-2018, 04:52 AM
RE: Mike Osc AM radio transmitter? - by David - 02-01-2018, 09:29 AM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-01-2018, 03:03 PM
RE: Mike Osc AM radio transmitter? - by Arran - 02-01-2018, 10:04 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-15-2018, 11:35 AM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-15-2018, 11:55 AM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-15-2018, 10:43 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-17-2018, 06:37 PM
RE: Mike Osc AM radio transmitter? - by 35Z5 - 02-23-2018, 11:03 AM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-23-2018, 07:37 PM
RE: Mike Osc AM radio transmitter? - by 35Z5 - 02-23-2018, 09:28 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-24-2018, 02:05 PM
RE: Mike Osc AM radio transmitter? - by TV MAN - 02-24-2018, 06:01 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco 91 Speaker Replacement
The spider is glued on the cone and so is the voice coil. I think you can use a cotton swab dipped in acetone and carefu...RodB — 02:42 PM
Restoring Philco 37-604C
Yes I saw that. If I knew, I'd probably try to arrange for getting it myself. But I have just got one. Which does not m...morzh — 01:44 PM
Philco 38-2 Automatic Tuning
When you push the lever, you are supposed to rotate the disk to the desired station. Then the magnetic tuning will acqu...morzh — 01:42 PM
Philco 38-2 Automatic Tuning
I figure out the muting from another picture that helped. Now I need to know how the automatic tuning works. When I push...dconant — 12:11 PM
Philco 91 Speaker Replacement
How would I go about removing the spider from the cone?dconant — 12:04 PM
Philco 38-2 Automatic Tuning
Hello, I am having trouble getting my automatic tuning to stay unmuted. If I play with the tuning handle I can get it to...dconant — 10:51 AM
Does anyone make photofinish replacements?
Here’s the link to the DIY photofinish section of our site: klondike98 — 09:46 AM
Delco car radio Peko vibrator converstion issues
Hi Richard, Thx for posting the schematic.  As I remember as a kid, these were great performers for the time, likely...MrFixr55 — 08:56 AM
Delco car radio Peko vibrator converstion issues
hello mr Fixr, The Electro  Powersupply that I am powering the radio with has a huge choke plus a 10,000ufd electrolyti...radiorich — 10:58 PM
Delco car radio Peko vibrator converstion issues
How about putting a choke in the power supply? The big cap was likely an attempt to stabilize the DC. Kids who cre...MrFixr55 — 09:19 PM

[-]
Who's Online
There are currently 2991 online users. [Complete List]
» 2 Member(s) | 2989 Guest(s)
AvatarAvatar

>