Bluetooth Tube Radio Receiver No.6 "Completely Portable
Intro: Bluetooth Tube Radio Receiver No.6 "Completely Portable
The sixth project is The Portable Tube Radio.
I once made some battery operated portable amplifiers. But they anyway needs wires to connect sources and speakers, because there was no such way to connect source without wire then. But now we've got Bluetooth, I have realized my long-cherished dream.
STEP 1: The Receiver
RCA Victor 45B is a portable radio receiver.
Before the birth of transistr radio, there were many kind of such battery tub radio.
Battery tube needs 2 Power supply, "A" is for fillament, low (1.5 or 3V) voltae high current and "B" is for tube's anode,High vlotage(45 or 67.5V) low current. Around that time all of portable radios have two batteries in them.
STEP 2: Tubes
3A5 is a twin triode for high frequency
5676 is subminiatut battery tube for high frequency
These battery tubes are filament cathode type, so Every filament circuit should be isolated.
STEP 3: The Circuit
Parallel push pull with triode connection.
STEP 4: Ingredients
2.Vacuum tubes
i) 3B4 (miniature battery tube for transmitter) * 4
ii) 3A5 (miniature battery tube :twin triode) *1
iii) 5676 (subminiature battery tube;triode) *1
3.Lithium ion Battery 12V
Nowadays there are small,high efficient and cheap isolatd DC-DC convers. so we can build battery tube device with single battery
4. Isolated DC-DC converters
5..PIC microprocessor 12F675 and a rotary encoder
6.Bluetooth audio module KRC-86B
7.output transformer (Ichikawa
8.12V 2.5cm fan *2
9.capacitors, resisters, universal PCB, etc...
STEP 5: Disassembling
STEP 6: Build Amplifier Circuits
STEP 7: Controller
on/off : push tuning dial ( toggle)
FF/REW : turn clockwise/counterclockwise
STEP 8: Heat Exhaust System
Unless lithium battery prohibit heat, it would explode! ,So heat exhausting system is absolutely needed.
Make windows and set fan and partition.
8 Comments
mskogly 8 years ago
robot797 8 years ago
can you supply the scematic for the 100V power supply part
i am gonna upgrade my portable tube amp and i need a easyer way to get the high voltage (a bunch of 23A battery's aint gonna do it)
yaaaam 8 years ago
it had very poor efficiency, so i have never made since then.
The neatest way is using step-up DC-DC converter. but I cannot find on the web one that can output more than 100V.
The second best is stack isolated DC-DC converters. such as : http://www.minmax.com.tw/_english/01_converter/01_list.php?page=10&MID=3
Stacking four 24V converters, you would get 96V (sorry, I have not tried yet)
yaaaam 8 years ago
I used in this instructables a step-up DC-DC converter IDEC "PSR-BE03 qpp-12". Though it had been discontinued long before,
there are many kind of step-up DC-DC converters, such as
http://www.aliexpress.com/item/High-Quality-Boost-Converter-Step-up-Module-Power-Supply-600W-DC-DC-10V-60V-to-12V/2045983554.html
The simplest way is using car inverters. you can find them in automobile parts store or online store. Rectify their output you can get 150-300V DC with adequate current.
robot797 8 years ago
600W is a lot for a tube amp that only needs a few ma
sdyette 8 years ago
I'm inspired with this one, and you didn't over-explain for the "paint by numbers" crowd. Thanks!
yaaaam 8 years ago
Thank you .
I cannot find no amusement in the kinds of paint by numbers too, and Different from painting it is sometimes dangerous for beginners. The most dangerous thing is doing something without recognizing himself what he is doing, I think.
Edward Phantom 8 years ago