There are a variety of challenges in interfacing radios, computers, data interfaces, cabling interfaces and antennas. All have to be addressed individually, but sometimes it is hard to make choices when there are so many choices. Nothing wrong with home brew here .... Hi Hi
Two of the biggest oopppsss selections when we make our choices and put our money down is in the two areas of digital interfacing and rfi. ======================= Digital interfacing needs speed, lack of complexity, easy interface for keying and and moving audio around. Beware of external digital interfacing / switching that uses and external sound card in the device. This adds delay and unknowns in wave shaping. Though many will say that XYZ product with sound amplification built in works great and have never had any problems, that is ken to saying I have not had any problems with losing incoming emails. How do you know? External digital interfacing that use their own sound card in them, add delay to the audio path and to the switch circuits. Faster modes just wont work reliably under those conditions. VOX transmitter keying for digital modes is a poor way to perform this task, and allows for software generate sounds to enter the audio path. The SignaLink with VOX PTT is one of the units that has the problem being referred to. It does work alright for non critical ALE operation, but but does have occasional handshake failures and errors with the ALE. Some manufacturers of embedded ALE hardware radios require fast T/R switching. The SignaLink and other VOX type methods of keying PTT clip off the first part of the transmitted ALE waveform. VOX release delay cuts off part of the received signal at the beginning. PCALE can handle T/R timing better than some of the hardware ALE radios. If using VOX for PTT for digital modes like ALE / Multipsk operations, it is possible that you will not encounter too many handshake problems if the signals are strong, with out phase distortion and Qrm. It is also possible hat it will be impossible to link with some hardware ALE radios or carry on reliable information exchange. Handshake timing is too quick, and VOX start tones can not be used in software to key the Vox fast enough. A start tone will not fix the Vox Ptt timing issue either. Hardware PTT is unbeatable with it comes to PTT switching and keeping the operating system audio off the air. This is why I use the Rigblaster Data Jack Plug and Play USB interface with my TS-480HX. Dont forget the high stability crystal oscillator for your rigs. Narrow digital modes needs it, and most MARS require it. ======================= Other kinds of interfacing to radios these days is made a huge challenge due to the various kinds of cable connectors, and multi connectors meant to handle more cables than you can put on that connector! That is where I bring the LDG RCA-14 breakout box for the accessory jack on many rigs, such as my TS-480HX. The RCA-14 comes with a DIN-13, DIN-8, DIN-7, Mini DIN-8 and Mini DIN-6 cables. Compatible with these radios and many more: Icom: 703, 706, 718, 746, 756, 7000 and 7800. Yaesu: 817, 857, 897, and 840. Kenwood: 480, 570, and 2000. Ten Ten Orion and Orion II. http://www.ldgelectronics.com/products.php?cID=6&pID=21&v=1 ======================= RFI, we all have it at one time or the other. Most frequently we are also frustrated with efforts to fix it that doesnt work well on the HF bands. The reason is that most unmarked on sale RFI suppression components dont use Type 31 ferrite material. Basically we need to put ferrite 'RF' chokes on the lines and devices that we need to protect. Many readily available ferrite chokes, snap or slip on, are just not up to the performance we expected of them. Fortunately a newer line of ferrite material is available that is much more effective than what we normally have used. from the Fair-Rite site my eyes have been opened and better options are now available to contain these concerns. It is important that just because a ferrite slip on / clamp on is available to be used, doesnt mean it is up to the task for hf frequencies.... and sometimes it may take more than one device on a line or in a area. Look for up to date information online. Summary: Fair-Rite EMI Suppression Ferrite Cores Mouser Electronics 800 346-6873 Fair-Rite 2631480002 is a "bead" a little under 1/2" OD, 0.2" ID and 1" long. Beads (cylinders) Mouser Stock No 623-2631480002 Fair-Rite 2631665702 "beads", 0.687" OD, 0.375" hole, 1.125" long. Beads (cylinders) Mouser Stock No 623-2631665702 Fair-Rite 0431167281, 0.93" diameter, 0.4" bore, 1.55" long. Clamp On Cases Mouser Stock No 623-0431167281 Of course none of this works well if good (no not good, great) grounding with braid / strap strips are not used. Goggle searches will lead you to web sites with pdf files that have the specs for these items if your interested. ======================= Some devices such as my SDR-IQ have no audio interface to plug into to feed other software programs, such as a Dream Audio Mondale program, or other digital programs such as ALE or Multipsk. In other cases a program works fine in XP but due to audio handling differences in Vista, they dont work there. Frequently the work around is a virtual audio handling program such as VAC. With VAC installed programs see additional in and out audio lines that can be selected to provide the audio link paths needed. Virtual Audio Cable - http://software.muzychenko.net/eng/vac.html ======================= Last but not least is getting performance out of that computer to perform reliable digital mode operations. Steps that can be taken are: Dont run any programs that are not needed, especially audio video programs (as in cd / dvd programs). If your system has performance options, and may laptops do, choose the faster performing options over battery saving if needed. Turn off all program auto updates. Turned off all program search auto routines, especially auto find operations for your hard drive. Forced network to use G mode when wireless. Defrag hard drive. Adjusted priority of programs so they get more priority to run faster (task manager, select program, right click and set program priority and insure it has access to all cpu's). A biggie turned out to be turning on Hard Drive write caching. 73 from Bill - WD8ARZ
