Hello Amateur Radio World! We would like to announce that we have designed an innovative, high performance panadapter for the popular radio IC-9700. Product is designed by our professional RF Engineers, tested and verified in-house. PTRX-9700 is available now for ordering.
Radio Analog is a company founded more than a year ago and started designing innovative and high quality products for Amateur Radio World. Our first product was the PTRX-7300, which had great attention from the community and achieved an exceptional success. We have shipped many products through our reputable distributors all around the world. We have met a lot of good mannered radio amateurs and had happy users of our product during this time. After releasing PTRX-7300, we had been asked by hams if we can design a panadapter for IC-9700, which is sister of the IC-7300, both available side by side in amateur shacks. When queries happened often, we decided and started to design then prototyped PTRX-9700. Before going to full production, we have frozen the project for a while because we had copying and copyright infringements against our very first product PTRX-7300. We suspected if we would encounter the same scam in the upcoming products, then we have looked for taking serious measures. After this period, we resumed the project. Now we believe that it is time to introduce and go to the full production phase. As before, we will work again with our reputable distributors for best services, such as faster worldwide shipping, professional customer support, stocking spare parts, etc. We believe that it will be welcomed by the community and achieve a success as much as its predecessor PTRX-7300.
CONCEPT
A true panadapter is a device which replicates internal RF/IF signal of a radio without sacrificing performance and functionality. Moreover, it should be able to get integrated into the rig easily, so that anyone can manage to do it by their own without requiring any special skills, such as soldering, cabling, etc. Also, the installation process should be hassle-free and reversible. We have taken these requirements as major guidelines during the design process.
IC-9700 is a popular radio supporting 2meter, 70cm and 23cm amateur radio bands. It has separate antenna connectors for each band, but there is no interface to access internal RF/IF signals. Moreover, it has no any usable free space in rear panel to take out RF/IF signals of the panadapter, or no connector to be replaced with a smaller one to get some space for a new connector, as we did in PTRX-7300 design. At a first glance, it looks impossible to find a neat solution without drilling the case or modifying rear panel connectors of the radio. Nevertheless, after some brainstorming, we finally figured out how to do it in a neat way.
IC-9700 has a reference signal (10MHz) input at the rear panel as shown in Figure-1. This connector is the only one to use as a RF/IF output. But we didn’t want to remove or modify this connector; we had rather use it as a dual functioning port. It is assigned to keep functioning as a reference input besides being RF/IF output. Hence the reference (10MHz) and RF/IF signals are well separated in frequency; this was not technically a challenge for us, relying on our experience. For this purpose, we designed a custom frequency splitting network on the panadapter PCB and an additional standalone splitter board to inject reference signal externally. If you don’t need to use reference input of the radio, you don’t have to use this external splitter, but it will still be included in a standard panadapter kit.
Figure-1
DESIGN
Block diagram of the PTRX-9700 is shown in Figure-2.
Figure-2
Figure-3
IC-9700 digitizes 2meter and 70cm bands directly while down-converts 23cm band into IF band. 2meter band spans between 144-148 MHz, 70cm band spans between 430-450 MHz and 23cm band spans between 311-371 MHz in the IF band, respectively. Fortunately, these signals are available on the U.FL connectors located on the main board of the IC-9700 and easily accessible. PTRX-9700 actively probes and conditions these signals via amplifier blocks as shown in Figure-1. Amplifier blocks are specifically designed for minimal signal loss, less than 0.3dB on the RF/IF signal path. After that, signals are combined, filtered, and multiplexed towards the output ports as REFout and OUT ( RF/IFout+ REFin). All input and output ports are shown in the Figure-3 via the CAD model.
Hence the reference and RF/IF signals are available on the same line (rear-panel SMA port), they should be separated outside if the reference input function is needed. This is done by a custom designed standalone “reference injection board” shown in Figure-4. As we mentioned before, this splitter only needed if you want to inject a reference signal to the rig, otherwise you don’t have to use this board and you can directly connect your SDR to the output SMA port.
Functional diagram of the external reference injection board is shown in Figure-5. As shown in the diagram, the board simply separates common port signal into RF/IF output and REF input. RF/IF port is connected to the SDR and REFin port is connected to the 10MHz reference source. There is more than 60 dB isolation between IF and REF ports, moreover reference frequency (10 MHz) and RF/IF frequency range are well separated. Hence, the signal splitting technique works perfectly for this case. Furthermore, reference frequency input bandwidth is designed to be more than 50 MHz to allow injecting 49.150 MHz GPS disiplined clocks. Please check Figure-14 for wiring diagram.
In Figure-6, 7, and 8, various SDR interface configurations are shown. In Figure-6, SDR is directly connected to the SMA port. In Figure-7 and 8, SDR is connected through reference injection board for the case of injecting reference signal to the radio.
Figure-4
Figure-5
Figure-6
Figure-7
Figure-8
KEY FEATURES of the PTRX-9700
- 4-Layer professional PCB design for best EMI (Electromagnetic Interference) performance.
- No need any modification at the rear panel, thanks to the dual functioning SMA connector.
- Super easy installation in minutes, only need a screwdriver and a tool (which is included in the kit).
- CNC machined special tool design to plug/un-plug tiny U.FL connectors safely.
- Panadapter PCB is directly screwed in the chasis of the radio for tight and secure mounting.
- No compromise in functionality and performance of the radio.
- Fully reversible installation.
WHAT IS INCLUDED IN THE KIT?
Figure-9
- Panadapter Main Board
- Reference Injection Board
- Mechanical Mounting Parts
- Power Cable
- UFL-F Cable Assemblies
- SMA-M/SMA-M Coaxial Cable
INSTALLATION
PTRX-9700 is designed specifically for easy installation. Only a screwdriver and a tool is needed which is included in the kit. This tool is specifically designed to ensure plugging/un-plugging of the tiny U.FL connectors of the radio safely. Because, if not taken care of properly, these connectors can be damaged during the installation. This is why we have designed this tool. During the development period, we installed and uninstalled the panadapter many times, but haven’t had any damage on the connectors, thanks to this tool. We don’t recommend using finger nails, screwdriver or any other objects to plug/un-plug these tiny connectors.
Panadapter board is directly screwed in the chasis of the radio with two screws diagonally. Because the PCB has the 4-layered rigid stack-up and size of the screws are big enough, mounted board is tight, secure, and strong as rock after mounting.
Mounting points are shown inside the yellow circles in the Figure-10. These screws are removed and replaced with the longer ones as shown in the Figure-9/Group-3. Also, the metal spacers (shown in the Figure-9/Group-3) are placed between the panadapter and the PCB of the radio in order to have enough clearance.
Power connector of the radio supplying DC voltage to the panadapter is shown inside the yellow frame of the Figure-11.
Figure-10
Figure-11
RF/IF signal cables (U.FL cables) and the power cable (Figure-9, label 4) are mounted as shown in the Figure-12 and installation is completed.
Figure-12
Figure-13
Figure- 14 Reference Injection with Leo Bodnar Board
TEST and VERIFICATION
We design and test RF products in-house. In our RF laboratory we have Agilent Spectrum Analyzer, Wideband 6-GHz Real Time Oscilloscope, Network Analyzer, Signal sources, and many accessories. We are in favor of low cost SDRs (such as RTL-SDR, etc.) to introduce SDR technology in a budget however we do not use these limited capacity products to design and test something. Because, these SDRs can easily hinder the real performance of what you are designing. If you want to design a high performance product you need spectrum analyzers, these SDRs cant help. You can’t expect similar performances from two hardwares, one is 10$ other is more than 60K$. Likewise, we don’t connect an antenna to the input of the radio and demodulate some signals on the air, assuming what we designed is working properly. Owing to the ambient noise and broadcasting stations, the accurate measurement of the device under test will become ambiguous. Instead of this inadequate approach, we create a controlled environment with the high purity signal sources and signal analyzers. Laboratory grade equipment such as spectrum analyzer, network analyzer, oscilloscope, signal sources are required for this purpose.
In the video below, a sample operation of the PTRX-9700 is given. In this test, real time sweep of the 23cm band is shown at the panadapter output. A sweep signal of 1240-1300 MHz is applied to the antenna input of the IC-9700 and the panadapter output at the SMA port is monitored. At the same time 10 MHz reference injected to the radio through reference injection board to see if there is any coupling/interference. As can be seen in the video, signal is stable and clean across the 311-371 MHz IF band which is widest compared to VHF/UHF bands. At the midst of the video, sweep signal and the tuned frequency of the IC-9700 coincide, it is demodulated and a beep sound is heard.
To demonstrate the external reference injection capability, the reference injection board is connected to the SMA port at the rear panel and 10 MHz reference is injected into the REF port of the splitter. As it is seen in the Figure-15, signal is perfectly transferred to the internal reference port of the IC-9700 with minimal loss.
Figure-15
PTRX-9700 has been started to be shipped, please contact to our distributors for orders.
Your comments, feedbacks and questions are welcome. Please email radioanaloginfo@gmail.com. Thank you !