SpinCore PA10W RF Power Amplifier Owner’s Manual
- June 6, 2024
- SpinCore
Table of Contents
SpinCore PA10W RF Power Amplifier
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© 2021 SpinCore Technologies, Inc. All rights reserved.
SpinCore Technologies, Inc. reserves the right to make changes to the
product(s) or information herein without notice. RadioProcessor™,
PulseBlaster™, SpinCore, and the SpinCore Technologies, Inc. logos are
trademarks of SpinCore Technologies, Inc. All other trademarks are the
property of their respective owners.
SpinCore Technologies, Inc. makes every effort to verify the correct operation
of the equipment. This equipment version is not intended for use in a system
in which the failure of a SpinCore device will threaten the safety of
equipment or person(s).
Precautions
Working with RF power amplifiers can be dangerous and even fatal if not handled properly. Output voltages can reach values greater than 90 V peak-to- peak and can be fatal. Follow these steps to avoid damaging the amplifier or inflicting serious injuries.
Connecting & Disconnecting Power Amplifiers
When connecting the power amplifier, follow these steps to avoid damaging the amplifier or inflicting serious injuries.
- Apply the load to the amplifier (make sure a load is ALWAYS present when working with power amplifiers).
- Apply the DC power to the amplifier.
- Apply the RF input to the amplifier.
Repeat the steps in reverse order when disconnecting the amplifier.
Power Considerations
Make sure the following considerations have been made before applying power to the amplifier.
- Be sure your load can appropriately dissipate the maximum power being applied by the amplifier.
- When applying an RF signal, work with low duty cycles to limit the power being dissipated. The duty cycle ratio should be below 1% for safe operation.
PA10W – 10 W Power Amplifier Modul
Overview
The PA10W RF power amplifier comes in a very compact broadband module
delivering 10 Watts RMS (20 Watts PEP, Peak Envelope Power) into a 50-ohm
load. It has a 3 dB range of 10 MHz to 75 MHz and is powered by a DC +12 V
power supply (with the negative terminal grounded). The PA10W has standard
female SMA jacks for RF input and output, and a standard 4-pin ATX connector
for the input DC power. The PA10W typically operates in Class AB. The rise and
fall time for the RF pulse output is typically around 200 ns.
The product comes with blanking circuitry – the blanking circuitry keeps the
PA10W blanked (turned off) until a TTL input (logical high) is applied to
deblank it. The blanking circuitry helps to conserve power, keeps the
amplifier cool under typical operating conditions, and provides noise
reduction during the reception of NMR signals.
The PA10W module measures 2.25″ x 1.4″ x 1.4″ (57 x 36 x 36 mm). There are
multiple ordering options available, such as enclosures with integrated AC
power supplies and enclosures with a complete RF front-end with preamplifiers
and filters for a complete mobile NMR, NQR and MRI system. See the
“Configuration Options” section later in this document for more information.
The use of a low pass (or band pass) filter at the output of the PA10W is
recommended to reduce high frequency noise and improve performance.
Electrical Specifications
| Parameter | Specification | Units |
|---|---|---|
| Max DC Input Voltage | 12 | V (DC) |
| Max RF input power | 40 | mW |
| Max. continuous RF output power | 10 | W (RMS) |
| TTL Deblanking Voltage | 3.3 | V |
Table 1: Basic electrical specifications for the PA10W power amplifier module.
PA10W RF Module with Deblanking Circuitry
This configuration shown in Figure 1 does not have an enclosure and includes
the switching circuitry mounted on top of the power amplifier to enable it
when a TTL pulse is applied to the input pin. This feature reduces power
consumption and keeps the power amplifier cool. 
RF Input and Output Connectors
A top view of the PA10W module depicting RF input and output connectors is
shown on the next page in Figure 2. When connecting the PA10W power amplifier,
the RF signal source should be connected to the SMA jack on the right hand
side (top view) of the circuit (RF in). The SMA jack on the left hand side
(top view) is the RF output from the power amplifier (RF out).
Diagram of power amplifier RF
connectors (top view). RF out and RF in are SMA jack connectors.
TTL Control Input Connector
The PA10W power amplifier module has a 10-pin shrouded male IDC connector1, also shown in Figure 2 above, which supplies the input TTL control signal. The control signal is pin 8 on the IDC header and the corresponding ground is pin 7. The input is terminated by a 100-ohm load and requires an external TTL signal source capable of outputting at least 10 mA. The TTL requirements for the deblanking control input are standard low voltage TTL values of 3.3V for a logical high, 0V for a logical low. A logical high signal is required to deblank (enable) the PA10W. The deblanking bit must be set at least 3 ms prior to sending the RF signal or optimal power will not be achieved. 10-pin IDC connector (Digi-Key part A33159-ND). Mates with Digi-Key part HKC10H-ND or similar.
Note: The deblanking TTL input header is denoted P2 on the circuit board. Please see Figure 3 above, for pin diagram. The circuit board may have another 10-pin shrouded male IDC connector denoted as P1 which is used internally to adjust the output voltage to the power amplifier.
The timing diagram of a typical application of PA10W with the deblanking pulse
applied prior to the RF pulse is presented in Figure 4 below. When working
with short RF pulses, on the order of 1 us or so, triggering the oscilloscope
on the falling edge of the deblanking pulse will help with identifying and
capturing the RF pulse on the scope.
Representation of the deblanking and RF input and output
signals to the PA10W. The PA10W requires at least 3.0 ms of deblanking time
prior to the RF pulse for full output power.
The performance of the PA10W at the end of the pulse is presented in Figure 5,
below.
Typical
performance of the PA10W at the end of pulse. Channel 2 is the deblanking
signal and channel 1 is the RF output. The PA10W was driven by a 2.6 V peak-
to-peak RF signal with the output signal attenuated 20 dB and terminated with
50 Ohms.
DC Power Input Connector
The PA10W RF power amplifier has a 4-pin input power connector. The input is for use with a standard PC ATX power supply connector. The pin arrangements for this connector are shown on the next page in Figure 6. 4-Pin input connector (Molex part 0531090410). Mates with standard PC power supply connector or Molex part 0015244048.
PA10W RF Module Enclosure Options
The PA10W RF power amplifier module can be delivered in various external enclosures which protect the RF power amplifier circuitry and include an AC/DC power supply, internal RF cables and output low-pass (or band-pass) filter (please specify your operating frequency at the time of purchase). The power input is 90-264 V AC, the RF input/output signals are provided on external BNC connectors, and the TTL inputs are routed through female DB-9 input connectors. The active TTL signal needs to be connected to pin 4, with the corresponding ground line connected to pin 8. Three standard enclosure configurations are available:
- PA10W module in a single bay enclosure (Figure 7)
Single bay enclosure additional specifications include:- Excellent EMI/RFI shielding which meets FCC & CE regulations.
- Built-in 4×4 cm quiet cooling fan.
- High quality 50 Watt AC input switching power supply.
- Dimensions are approximately 10.25” x 7.75” x 2.25” (26 x 19.5 x 6 cm).
- PA10W module enclosed with iSpin-NMRTM system (Figure 8)
iSpin-NMR enclosure additional specifications include:- Metal body with streamlined plastic front panel.
- Built-in 8×8 cm quiet cooling fan.
- High quality 80 Watt AC input switching power supply.
- Dimensions are approximately 11” x 7” x 6.75” (28 x 18 x 17 cm).
- PA10W module in Lightweight aluminum enclosure (Figure 9)
Small aluminum enclosure additional specifications include:- Lightweight aluminum enclosure.
- High quality external 60 Watt AC input switching power supply.
- Dimensions are approximately 4” x 2.4” x 3” (10 x 6 x 8 cm).
- PA10W RF in enclosure with Preamplifier Option
The enclosure can also include input preamplifiers (approx 45 or 60 dB of gain – please specify when ordering) to the RadioProcessor board. This option is perfect in combination with the iSpin-Mini system to provide a complete mobile NMR system (see Figure 10).
Related Products and Accessories
- Alternate power levels available: 15 W, and 75 W. For more information, please visit the URL http://www.spincore.com/products/RFPA/
- iSpin-NMR, The Complete, Simple, Intuitive, Effective and Portable NMR System. For more information, please visit http://spincore.com/products/iSpinNMR/
- Complete single-card solution for RF pulse generation and acquisition, the RadioProcessor. For more information, please visit http://www.spincore.com/products/RadioProcessor/
- NMR Permanent Magnets are available for conducting NMR experiments. For more information, please visit http://www.spincore.com/products/Magnets/
- If you require a custom power level, please inquire with SpinCore Technologies through our contact form, which is available at http://www.spincore.com/contact.shtml
Contact Information
SpinCore Technologies, Inc. 4631 NW 53rd Avenue, SUITE 103 Gainesville, FL
32653
USA
Telephone (USA): 352-271-7383
Website: http://www.spincore.com
Web Contact Form: http://www.spincore.com/contact.shtml
Document Information
Revision history available at SpinCore.
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