DL manuals
MagicBox
Transmitter
V1R2B
Assembly Manual

MagicBox V1R2B Assembly Manual

Manual is about: Solid State Transmit/Receive System

Page of 20

Download

Print this page

Bookmark us

Assembly Manual

V1R2B-Rev1.0D

for 4 State QRP

MagicBox

- Solid State Transmit/Receive System

This system is the result of some brainstorming with Terry Fletcher, WA0ITP and Joe Porter, W0MQY

at the Dayton Hamvention in 2009. We were talking about kits that might be suitable as revenue

generators to fund the Ozarkcon activities in 2010 and beyond. The "MagicBox" project is the result.

It is an all solid state, Transmit/Receive switching system that allows one to connect single band CW

transmitters (up to a maximum of 10 watts) and receivers together to turn the pair into a transceiving

station, "like magic". The system can be used on any band from 160 through 10 meters. It can handle

both solid state and cathode keyed, tube transmitters. It supports full QSK CW up to about 50 WPM.

And, a non-QSK mode is also provided, for those who don't like QSK CW.

There are five pieces of functionality within the system. First, is a keying circuit to turn on the

transmitter. Second, is a PIN diode switch used to connect the transmitter to the antenna so that it can

transmit and also to isolate the output impedance of the transmitter from loading the receiver. Third, is

a four element, series-shunt switch that disconnects the receiver from the antenna and shorts the

receiver input to ground while the transmitter is transmitting. Forth, is another series-shunt switch

(three elements) used to disconnect the receive audio from the speaker (headphones) during transmit.

Fifth, is an sine wave audio oscillator and series switch that supplies side tone audio to the speaker

(headphones) during transmit so that transmit keying can be monitored. All of the control timing for

the system is supplied from an AVR ATtiny2313 microprocessor.

1 2 3 4 5 6 7 Next › »

Summary of V1R2B

Page 1
Assembly manual v1r2b-rev1.0d for 4 state qrp magicbox - solid state transmit/receive system designed by: jim kortge, k8iqy copyright 2009-2012 - all rights reserved this system is the result of some brainstorming with terry fletcher, wa0itp and joe porter, w0mqy at the dayton hamvention in 2009. We...
Page 2
The next pages contain an image of the supplied printed circuit board and the schematics for the system. 2.
Page 3
3.
Page 4
4.
Page 5
Pcb stuffing stuffing the pcb will be done by installing all of the connectors and headers. Following that, all of the resistors will be installed, starting from the lowest value and proceeding to the highest. Then, all of the capacitors will be installed, using the same scheme. That will be followe...
Page 6
Your pcb should look like this: resistors [ ] install the large, 1 watt, 180 ohm (brown-grey-brown) resistor at r12. This is the only 1 watt resistor; all of the others are 1/4 watt. Note: the leads of this resistor should be bent as shown in this detailed photo, so that it will fit the hole pattern...
Page 7
[ ] install the 1k trimmer resistor (blue potentiometer) at r32. Your pcb should now look like this: capacitors [ ] install 0.02 uf (green color - marked 2a203k) at c19, c20 and c21. [ ] install 0.1 uf (tan color - marked 104) capacitors at c1, c5, c6, c7, c8, c9, c10, c11 and c12. [ ] install 2.2 u...
Page 8
Your pcb should now look like this: 8.
Page 9
Inductors/transformers [ ] install 100 uh (beige color - marked brown-black-brown) molded inductors at l1, l3 and l4. These look a bit like fat, 1/4 watt resistors. [ ] wind and install transformers t1 and t2. The "winding t1 and t2" page contains notes on winding these transformers, along with some...
Page 10
Diodes [ ] install the 1n5818 (black body - marked 1n5818) diode at d1. [ ] install the 1n459a (black body - marked 1n459a) diode at d2. Save one lead from this diode so that it can be used as a jumper on the ic socket u1 later on in a testing stage. [ ] install the 1n4007 (black body - marked 1n400...
Page 11
Regulators (look like transistors with 3 leads) [ ] install the 10 volt (black body - marked 750l10c) regulator at ic1. [ ] install the 5 volt (black body - marked 750l05c) regulator at ic2. [ ] put the supplied 2-pin shorting shunt on header j14. Apply 12-15 volts dc to j1 and check that the left p...
Page 12
Transistors transistors will be installed in groups so that testing can be performed. After successful testing, the next group will be added. Using this approach will ensure that the completed project works as designed. [ ] install 2n3904 transistors at locations q14 and q15. [ ] install a 2n7000 tr...
Page 13
[ ] write down your results/observations_________________________________________________ _________________________________________________________________________________ [ ] install a 2n3906 transistor at location q4. [ ] install 2n7000 transistors at locations q5 and q8. [ ] install a 2n7000 tran...
Page 14
Operational checks if an rf signal generator is available, connect it to the antenna out bnc connector j3. If no signal generator is available, connect an antenna to j3. Using a bnc jumper, connect the antenna lead of a receiver to the receiver out connector j2. Connect a key to the key(er) connecto...
Page 15
With both receiver and transmitter connected to the magicbox, key the transmitter several times and assure that the receiver is being muted except for the sidetone and the transmitter is keying properly. [ ] write down your results/observations_________________________________________________ ______...
Page 16
Connection diagram note: the audio connection from the receiver should be wired to the magicbox using a stereo plug on the magicbox end, with the ground on the ring terminal and the signal lead on the tip terminal. The j5 and j6 jacks should have their mounting barrels insulated from chassis ground ...
Page 17
Packaging considerations now that you've completed your magicbox t/r system, you may have decided to put it into some kind of enclosure. This document will aid your efforts in doing that. However, just so you know, it will work just fine without being in an enclosure; it was designed to work "out in...
Page 18
Magicbox specifications general system 160 through 10 meter operation 5.3" x 4.0 " pcb, fits tentec tp-41 case approximately 120 parts beginning builder skills level project construction time approximately 8 hours power supply 10-15 volts dc; 120 milliamps rf section receive mode antenna to receiver...
Page 19
Bill of material 19.
Page 20
Instructions for winding t1 and t2 start by marking each core with a "dot" on one end using a blue "sharpie" marking pen. Touch the spot several time to make sure that a permanent dot exists. This "dot" end by our convention will be the secondary side of each transformer, and have a 2-turn winding o...