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TWT is a travelling wave tube, they amplify. Tunnel diodes also, betcha you could make a parametric amp out of one of those tiny schottkies.

http://ams.aeroflex.com/Meteli...

At that point the connectors are lossier than the gain maybe...

They go well over 25 MHz. For instance, here is a LEON-FT based chip that goes up to 66 MHz. There are also other chips that can be clocked at 100MHz+.

My wireless card software can already show me the signal-to-noise levels on all the channels so I fail to see what else that thing can do in addition. And if you insist on seeing a quite useless image of the 'spectrum' then there are free software for that out there already such as Kismet.

The comparison on their website is just silly. You can rent a basic spectrum analyser for a couple of hundred dollars for the day, plug in a directional antenna to your test port and pinpoint your problem, as well as use the tracking generator and a reflection bridge to test all your wireless equipment, tranceivers, cables, antennas, adapters/connectors etc. for attennuation, SWR, passband etc. Having installed a load of wireless stuff just as a hobby I find that thing quite useless.

The motors seem to be right out of the Maxon catalog, with the planetary gearhead option on one end and the encoder on the other. Those are good motors (we used one to steer our DARPA Grand Challenge vehicle), but they are not rated for spacecraft operation.

Here's an Aeroflex gimbal that actually is used in space to steer a thruster. Note how the rotational axes go through the line of thrust, and how big and solid the bearing blocks are, compared to the proposed design.

What kind of towers are you checking - cell, LMR, broadcast, Ham?

Perhaps you'd used gear I've designed?

What kind of towers are you checking - cell, LMR, broadcast, Ham?

Perhaps you'd used gear I've designed?

What kind of towers are you checking - cell, LMR, broadcast, Ham?

Perhaps you'd used gear I've designed?

1. The only constant is change - specs change, languages change, chips change. At two years you haven't seen as much change, and you think things are relatively static.
2. Macro-optimization. Suppose you have a program that does lots of string compares (like a language parser). At 2 years experience you probably would try things like inlining the string compare, or the "if (a[0] == b[0]) return strcmp(a,b); else return -1" trick. At 10 years you do things like making your String objects have a hash code and doing a simple single int compare. In other words, you learn to optimize ALGORITHMS, not implementations.
3. Compilers lie. At two years you think the problem MUST be in your code, because you have not yet learned that compilers have bugs, and sometimes mis-compile things. At ten years you learn that most of the time you screwed up, but SOMETIMES the compiler screwed up - so you get a mixed assembly output and doublecheck
4. Neo-phillia. At two years you jump on every new thing, because you think it simply MUST be good. At ten, you learn to sit back, evaluate, and then implement in an experimental context.
5. Documentation. At two years you hate doing documentation. At ten you hate doing documentation, but you hate NOT HAVING DOCUMENTATION EVEN MORE.
6. Project maintainance. At two years you figure if it can be compiled on your machine, good enough. At 10, you learn to make the build proceedure as easy as possible, so that newbies can come on the project quickly, and so that you can recreate the project easily after several years of inactivity.
7. The difference between being productive and being busy. At two years, you think that working 60 hours a week, always in crisis mode is being productive. At ten, you learn that the most productive people get more done in 40 hours a week, calmly. Crisis are to be avoided by forsight.

As another poster asked, define "rural". I live 10 miles outside of Wichita, KS. Prior to 1997 the 2 acre lot my house is on was a wheat field. I have DSL, yet heat with propane, use well water, and have a septic field rather than city sewer. Rural enough? Yet I have a 9 minute commute to work.

I work at a leading communications test equipment company doing DSP, embedded software, and UI design in TCL/Tk. I get to play with 10 million gate FPGAs, 60MSample/second digitizers, microwave comms gear, and stuff that I am not allowed to talk about.

Check out our job offerings - you might just fit.

Now, just up the road (I35, to be exact) is Olathe, KS - a suburb of Kansas City, (KS|MO), wherein there are SEVERAL high-tech job centers.

Down the road is Oklahoma City - again, a city with a fair number of tech jobs, wherein one may live outside the city yet commute without too much difficulty.

Beleive it or not, not all tech development goes on on the coasts. Do a bit of research.

1. No timing skew. With a high speed parallel bus, you have to insure that all the data paths are the same electrical length, or else some bits get to the card before other bits, and you have to reduce the clock rate to prevent errors. With a serial system you have far fewer lines to worry about.
2. Simpler board design. When you are dealing with a 64 bit data bus, 64 bit address bus, plus control lines, the board design gets a bit complex. With a serial system, you have less than ten lines per channel - a much simpler board layout.
3. Serial systems usually use a MUCH lower signaling voltage, resulting in MUCH lower EMI and on-board noise.
4. PCI express allows you to gang serial channels for more bandwidth. Video card saturating one channel? Use two.
5. Unlike AGP, PCI express is a bus - so each device can busmaster to system memory or to other cards as needed. This helps you when your video card wants to store textures in system RAM rather than on-card. Imagine how much fun John Carmack could have with a video card that can support 1G of textures.
6. It is far easier to design disconnects for a serial bus, thus allowing for PCI hotswap. In fact, the PC card group is working on a new standard for PC cards (nee PCMCIA) that brings 2 PCI-X channels to card - Cardbus on steroids.
7. It is possible to route a PCI-express channel out of the computer case to an external chassis. While this is of limited use to the usual computer user, for guys like me it is a boon to be able to have an external chassis that looks just like it is on the main system bus, because it IS.

OK, this whole thing confuses me, and I am an embedded systems engineer. I've seen this in the trade journals, and I don't get the marketing forces this is supposed to answer.

Consider this: my old laptop that I purchased in 1996 had 3 PCMCIA slots. This was good - I could have my NIC, my SCSI card (for tape backups), and my modem all in place at the same time.

However, any laptop of recent vintage will have at least USB2.0 High speed if not IEEE-1394 (FireWire), so this obviates the need for the SCSI card. It will have built-in Ethernet (at LEAST 10/100 MBits, if not 10/100/1000!), so there goes the Ethernet card. It will have a build in (Win)Modem, removing the need for the modem (at least for Windows users, and very likely for Linux users as well now-a-days).

So what is left for the PCMCIA slots? Flash readers? Built-in, or USB. Video capture? (like you need that in a laptop anyway, but....) Firewire. Video acceleration (MPEG decoding)? Faster CPU. 3D acceleration? Built in.

I can see using PCI-Express (the PROPER name for the new, high-speed serial interface) for the docking station interface - but even then, what do you really need to add to a laptop now?

So what is the point of a PCCARD style interface? OK, I may not be able to get a Firewire tape backup device (or maybe I can - I haven't looked since I don't need one), but if I want to back up a new laptop I can use the network or just dump everything to a Firewire drive.

Now, some may say "Yes, but what about embedded devices". And I can say, as a professional, "What about them?" Either what I am building is a small, simple device, where I would rather build in a USB 2.0 host adaptor, or it is a big, hairy multi-CPU monster that has what it needs built-in. Really, in neither situation would I want to go to the difficulty of adding a PCMCIA-style interface. Been there, done that, and had far too many headaches with people expecting to install J. Random Card and have it work. Sorry, but unless you are using Embedded Windows, you cannot just install the driver disk and go. And if you are using a Windows deriviative, you DON'T WANT users installing their own software (unless you really like watching Customer Service drown).

Again, unless we start seeing laptops with their video on a card, PCMCIA style interfaces are no longer the best engineering decision. Let them die.

OK, this whole thing confuses me, and I am an embedded systems engineer. I've seen this in the trade journals, and I don't get the marketing forces this is supposed to answer.

Consider this: my old laptop that I purchased in 1996 had 3 PCMCIA slots. This was good - I could have my NIC, my SCSI card (for tape backups), and my modem all in place at the same time.

However, any laptop of recent vintage will have at least USB2.0 High speed if not IEEE-1394 (FireWire), so this obviates the need for the SCSI card. It will have built-in Ethernet (at LEAST 10/100 MBits, if not 10/100/1000!), so there goes the Ethernet card. It will have a build in (Win)Modem, removing the need for the modem (at least for Windows users, and very likely for Linux users as well now-a-days).

So what is left for the PCMCIA slots? Flash readers? Built-in, or USB. Video capture? (like you need that in a laptop anyway, but....) Firewire. Video acceleration (MPEG decoding)? Faster CPU. 3D acceleration? Built in.

I can see using PCI-Express (the PROPER name for the new, high-speed serial interface) for the docking station interface - but even then, what do you really need to add to a laptop now?

So what is the point of a PCCARD style interface? OK, I may not be able to get a Firewire tape backup device (or maybe I can - I haven't looked since I don't need one), but if I want to back up a new laptop I can use the network or just dump everything to a Firewire drive.

Now, some may say "Yes, but what about embedded devices". And I can say, as a professional, "What about them?" Either what I am building is a small, simple device, where I would rather build in a USB 2.0 host adaptor, or it is a big, hairy multi-CPU monster that has what it needs built-in. Really, in neither situation would I want to go to the difficulty of adding a PCMCIA-style interface. Been there, done that, and had far too many headaches with people expecting to install J. Random Card and have it work. Sorry, but unless you are using Embedded Windows, you cannot just install the driver disk and go. And if you are using a Windows deriviative, you DON'T WANT users installing their own software (unless you really like watching Customer Service drown).

Again, unless we start seeing laptops with their video on a card, PCMCIA style interfaces are no longer the best engineering decision. Let them die.