SWEEP KIT CONSTRUCTORS
ALERT
There are no current issues to be announced.
For any issues with Faults or modifictions to the DDS board, please
refer to the EME85 KIT Page.
DOWNLOAD
A COMPLETE LIST OF PARTS INCLUDING HARDWARE FOR EXCEL, & EMAIL
US YOUR LIST WHEN ORDERING. SWEEP
KIT
BELOW SHOWS THE
BASIC SWEEP KIT1
The above Picture shows the complete
SWEEP KIT1. Please Note the above
picture does not show the EC12E encoder which is covered by the knob,
but is included.
WHAT WILL THE DDS &
SWEEP GEN SOFTWARE ALLOW YOU TO DO?
PLEASE NOTE:THE PIC ASM
OR HEX SOFTWARE IS NOT SUPPLIED WITH THE KITS OR AVAILABLE. WE ONLY
SUPPLY PRE PROGRAMMED PIC CHIPS.
Refer to the Software Notes for
more detailed information Use, Download the Sweep Readme
document.
The Software is designed to be used
for a simple signal generator, but also has an inbuilt sweep function
with the addition of the Power Head Kit can also measure RF Power in
dBm, Watts, Volts. Standard functions are Frequency Tuning, Step Size,
Calibrate, Memory, Sweep Direction, Sweep Start Stop, Sweep speed, Fast
Sweep, VFO/Sweep mode. The signal generator output can be used at the
same time as reading RF from one of the Power Head Kits. So a filters
3dB BW can be measured by tuning the DDS generator by hand looking for
the -3dB points of the filter. The Sweep function is only suitable for
use with either a Spectrum Analyzer or Oscilloscope with a RF probe
as the sweep is too fast for the power head kits to read. Currently
there is no trigger pulse available from the sweep generator for locking
of an Oscilloscope.
The software does not allow for
any display offset or Transceiver Radio functions, as it has been designed
to make a useful piece of test equipment. A DDS suitable for building
a Transceiver is the DDS Kits 1 2.
BASIC SOFTWARE SPECIFICATIONS
1/ Frequency range programmable
from a minimum frequency of 1Hz, to a Maximum output frequency of 60MHz,
( Using a Osc4 30MHz osc module & DDS x6 multiplier
).
2/ Variable Rate Tuning & Adjustable
Step Size 1Hz, 10Hz, 100Hz, 1kHz, 10kHz, 100kHz, 1MHz, 10MHz, 100MHz,
1GHz etc
3/ Programmed to use a low cost
Mechanical Rotary Encoder.
4/ Software fine tuning of the Reference
oscillator frequency.
5/ Programmable for various Reference
oscillator frequencies & DDS x1 or x6 Multiplier.
6/ Up to 11 Sweep Generator Memories
can be programmed, ( Including start & finish
frequency, & sweep rate ).
7/ There are two Sweep modes Slow
& fast, in each there are 10 sweep speeds.
Slow sweep mode.
| 0 |
10 Hz |
per sec |
5 Hz |
per step every |
1/2 sec |
|
|
| 1 |
30 Hz |
per sec |
15 Hz |
per step every |
1/2 sec |
|
|
| 2 |
100 Hz |
per sec |
25 Hz |
per step every |
1/4 sec |
|
|
| 3 |
300 Hz |
per sec |
75 Hz |
per step every |
1/4 sec |
|
|
| 4 |
1 KHz |
per sec |
125 Hz |
per step every |
1/8 sec |
|
|
| 5 |
3 KHz |
per sec |
375 Hz |
per step every |
1/8 sec |
|
|
| 6 |
10 KHz |
per sec |
1.25 KHz |
per step every |
1/8 sec |
|
|
| 7 |
30 KHz |
per sec |
3.75 KHz |
per step every |
1/8 sec |
|
|
| 8 |
50 KHz |
per sec |
6.25 KHz |
per step every |
1/8 sec |
|
|
| 9 |
67 KHz |
per sec |
8.20 KHz |
per step every |
1/8 sec |
|
|
Fast sweep mode.
| 0 |
12 Hz |
per sec |
50 Hz |
per step every |
Step Every 4.096mS |
|
|
| 1 |
37 Hz |
per sec |
150 Hz |
per step every |
Step Every 4.096mS |
|
|
| 2 |
60 Hz |
per sec |
250 Hz |
per step every |
Step Every 4.096mS |
|
|
| 3 |
180 Hz |
per sec |
750 Hz |
per step every |
Step Every 4.096mS |
|
|
| 4 |
300 KHz |
per sec |
1250 Hz |
per step every |
Step Every 4.096mS |
|
|
| 5 |
1 MHz |
per sec |
3750 Hz |
per step every |
Step Every 4.096mS |
|
|
| 6 |
3 MHz |
per sec |
12.5 KHz |
per step every |
Step Every 4.096mS |
|
|
| 7 |
9 MHz |
per sec |
37.5 KHz |
per step every |
Step Every 4.096mS |
|
|
| 8 |
15 MHz |
per sec |
62.5 KHz |
per step every |
Step Every 4.096mS |
|
|
| 9 |
20 MHz |
per sec |
82.0 KHz |
per step every |
Step Every 4.096mS |
|
|
8/ Memorises the last frequency on power up.
7/ Calibration menu to program optional
Power Head Kits.
8/ Programmable menu to set for
when using an input attenuator or amplifier on the Power Head.
Refer to the Software Notes for
more detailed information & Use, Download the Sweep Readme
document.
The Sweep Generator Kit
above uses Takachi Aluminium Box ( 150x100x120mm ) RS Components 401-8982.
The front panel was cut out using a nibbling tool & filed with a
very fine metal file.
| PARTS
LIST 1.
1 x Power Switch (
SWITCH2 ) Toggle Type with Red LED different to
what is shown in the picture.
1 x 16x 2 LCD Display ( LCD1 )
1 x Knob 29mm suit 6mm shaft ( KNOB1
)
1 x 4 x 4 Keypad ( KEYPAD2 )
Included in Sweep Kits
|
1 x SMA Socket
( SMA17 )
1 x 4 Pin Mini XLR Chassis Plug (
MXCM4 )
1 x 4 Pin Mini XLR Line Socket ( MXLF4
) |
| PARTS
LIST 2.
1 x EME85 DDS Kit (
EME85 KIT )
1 x 70MHz LPF Kit ( 70MHz KIT )
1 x 30MHz Oscillator Module ( OSC4
)
1 x Control Board Kit ( EME159 KIT
)
1 x Connector KIT ( EME159 CONN
)
1 x SMA PCB Socket ( SMA09 )
1 x DC Jack 2.1mm (
DC JACK01 )
1 x DC Lead 2.1mm plug ( DC LEAD01
)
|
12x Bolt Panhead M3x6mm
( BOLT04 )
4 x Bolt Countersunk M3x6mm (
BOLT06 )
4 x M3 Star Washer (
WASHER01 )
1 x SMA R/Angle Plug (
SMA16 )
0.5 x ft RG316 Cable ( RG316 )
8
x 10mm Metal Spacers ( SPACER03
)
|
KIT FAULTS
& MODIFICATIONS
1/ Refer to the EME85
DDS Kit webpage for some possible problems.
2/ Most Faults can be traced
to poor solder joints, or solder bridges across connections. Check
for correct wiring to the control board & LCD display module.
3/ Low RF output on frequencies
lower than 15MHz is normally incorrectly fitted 10nF chip capacitors
on the input & output of the MAR6 amplifier. Some constructors
have accidentally put 10pF capacitors in place.
4/ Some have reported that when
using the Power Head kit on the Sweep Kit that the 0.1dB reading
flashes erratically on the LCD & cannot be read. The display
will normally change between 0.1dB steps as the meter display accuracy
is 0.25dB per step but can be quite easily read. Most problems with
this, has been traced to a noisy 12 volt supply to the Sweep Kit.
Make sure that you use a well regulated 12 volt Power Supply. The
problem only shows when using the DDS RF output & is not a problem
with another RF signal generator. I suspect that this is due to
the MAR6 on the DDS board generating the noise on the RF due to
there being no regulator on its supply.
5/ If you are getting erratic letters &
numbers, ( Garbage ) on the LCD, disconnect everything from the
DDS board excluding the LCD first. If the LCD is still showing the
same garbage on the display, then the software in the PIC is probably
corrupted & needs reprogramming.. There
has been one report of this.
|
Friday 13th November 09