Like I said before, if one does not know how to do it better don't do it. My systems have survived numerous events... never ever there was a plane related issue. But perhaps those generalizations like "cannot be done" "don't do it" etc. kind of thing are a valid practical advice after all. It can be done, but I suspect those who can do it won't be asking here how to do it.
Opera 8.54 allows you to choose. But you might like this free utility to speed loading. I used it on 5.05. Works like a charm:
PDF SpeedUp 1.42 (311KB, Freeware)
Speed up your Acrobat Reader to being lightning fast!
PDF SpeedUp allows you to significantly speed up the time it takes to load Adobe Reader. If you notice that when the Reader starts it loads many plug- ins which you may or may not need, this program simply disables the plug- ins and loads only the absolute necessary ones so the program starts quickly. It offers several options and you can also manually enable or disable the plug-ins as needed. PDF SpeedUp works with Acrobat versions 3 through 7. Multi-lingual interface:
Features:
Free PDF Tweak Utility for Adobe Acrobat v3.0 to v7.0, Adobe Reader 6 and 7.
Enable or disable the plug-ins as needed Turn off all Updates features Disable the splash screen during program startup Remove the My eBooks folder created in My Documents Turn off the advertisements for Adobe products in the upper-right corner of the toolbar Remove PrintMe and Adobe Reader icons Disable Browser Integration Disable confirmation dialog when closing Adobe Reader Better speed for LAN and Cable connection Clear Adobe Reader Recent Files History Restore to original settings at any time
my C:\\Program Files\\Adobe\\Acrobat 7.0\\Reader is 56Meg, I dont know what it all does but
C:\\Program Files\\Foxit Software is 4.4Meg, loads damn fast, very occasionally it can't read a pdf, so then I have to load adobe. But I never get messages like "adobe ver xx required"
Thanks, ive recently got a few nice Agilent MMIC from Farnel, one is a phemt type, also a start499 IC=600ma Ft=42ghz and a fairly large MW gaas FET to play about with. one MMIC seems to be non inverting with a very nice controlled gain to
3.5ghz and only 14ma ideal PA driver im even looking at making a very wideband MW VCO out of it, a 2nh inductor on the input to gnd and it oscillates very strongly, tuneable with finger from ~2-4ghz ! my attempts to control it more conventionaly with varicaps havnt yet been as succesfull as I wld like.
I learned from previous design to make the case of the laser connected to gnd to save heatsinks shorting out, and EMI. This meant having emitters tied to a negative rail instead of gnd wich also caused a problem, I think therefore I will AC couple the laser from a positive fed PA, and then have a very simple negative bias supply for the grounded laser, ... seemingly solving all the problems in fact a schottky diode could derive the negative bias from the RF if its over 3v pk pk Although this might be asking too much from the PA, I dont want to waste too much supply current. However it would give visible indication of a strong RF drive.
But the question still bothers me about the impedance of the laser and if I should try and match it or as you say and as I've done already just connect it so close to the driver to hope it doesnt matter too much. My laser diode measures ~ 60pf on my cap-o-meter although im not sure if it measures diode capacitance properly, spec sheet doesnt specify, but this seems absurdly high to be working ok at 1ghz, but its just a cheap pointer type diode, are special types for high frequency modulation that much better ?
Im modulating the bias of my apd with about 10v pk-pk at similar frequency too, this should be easier with these nice MMICs.
How much of that hittite device's 20ghz bandwidth do you use btw ?
-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | |
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| 1962 | I love to cook with wine. Sometimes I even put it in the food.
I have to admit, I was kind of surprised to learn that the purpose of a torque wrench is precisely that - so you don't _over_ tighten a given fastener.
At one tire place, I noticed the tire-kickers using a torque wrench on my lug nuts . I was impressed. It was awesome to see people doing their job right. :-)
At the Discount Tire locations around, everyone that I've ever got tire service in, the *manager* confirms torque on all lug nuts.
My guess is that, somewhere along the way, someone's wheel fell off ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Well, the multimode fiber sucks, but dispersion of a few ps/m doesn't translate to jitter of a few ps/m. My receiver bw is only about 200 MHz, so it takes more like hundreds of meters of fiber to start affecting things.
I'm just finishing up a 1310 nm singlemode link for some people who are concerned about this, now that I've finally found a source for affordable ST-housed Fabry-Perot 1310 lasers.
Actually, in the general case, low jitter doesn't require extremely wide bandwidth, just good s/n at a given bandwidth. Sometimes adding a lowpass filter can reduce jitter. The real problem with temporal dispersion is that it smears together, say, the first few ns of a laser pulse, and that few ns may include a lot of optical noise from the crappy vcsels everybody sells. If the top of the laser pulse were flat, the lowpass effect of the fiber wouldn't be as scairy.
And in real life, only a minority of customers really care about sub-100 ps jitter. Most don't care about 1 ns jitter.
A wheel fell off my MG Midget, in the middle of traffic on Mission Street, in downtown San Francisco. I left it in the middle of the street, walked back into the tire store, and screamed at them. They sent four guys with a jack to fix it, right in traffic. I double-check them myself now.
I understand that there isn't a 1:1 correspondence, but the mode dispersion can make for some pretty weird variations of delay with temperature and vibration.
Blowing a fuse can sometimes relieve a lot of tension and be fun too...
I had a 1964 Dodge Dart, new, just a few months old, and the wife was complaining that the brakes were grabbing.
So I took it back to the dealership.
They told me they couldn't find anything wrong.
So I drove it... the right rear brake was locking up.
So back to the dealership.
Again, they told me they couldn't find anything wrong.
Going home it locked up so tight that I slid sideways.
Fortunately, 42 years ago there wasn't anything in my way.
So I went on home, jacked it up... on a damned bumper jack... the only thing I had at the time.
Pulled the right rear wheel... the damned rear seal was leaking onto the drum brakes (1964, remember).
As I'm standing there cussing, the damned car starts to roll off the bumper jack.
I grab the car by the fender well and start screaming.
My wife can't hear me, she's inside running the washing machine... but I raised just about every male in the neighborhood. They stuck cinder blocks under it so I could let go.
I jacked it back up and replaced the wheel.
Returned to the dealership and started cussing at the top of my lungs... I often wonder how many sales I lost for them that day ;-)
But it got fixed... in a hurry.
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Actually, I've never used them. I'm usually working on/off, dc coupled, dc to hundreds of MHz at least, so there's no way to close the loop. On the receiver end, similarly, I usually can't use any of the pin/tia receiver packages because they almost always have agc that I can't disable, so I can't get clean response down to DC.
The fiber-coupled lasers I use seem quite happy with simple constant-current drive, but I usually output around a milliwatt optical-coupled power. Maybe the bigger lasers can grunch themselves if used this way.
You might try a delay-line oscillator, just a microstrip trace (or coax) from mmic output back to input, a tad below 1/2 wave long for an inverting mmic, which most of them are. That's fairly predictable and still varicap tunable some.
60 pF? Yikes! My 850 nm vcsels run under 2 pF typically. You would probably benefit from a tuned matching network.
We're running about 90 ps edges into our optical modulator, so 4 GHz roughly. The cheap EIC (W-J) mmics could almost hit our 100 ps risetime spec, but not quite. That last 30 ps or so cost us about $40K.
On my current project, I'm using an MC10EL89. I'm sinking a temperature-compensated constant current out of the laser cathode, and the '89 can pull that node up and turn off the laser. So I guess it's a laser un-driver.
I don't know yet; I just fired up the new driver board. We just recently picked up a 2 GHz RF signal generator on ebay (a Wayne Kerr) so I'll hook that up into the driver input and see what happens.
HTML might be a bitch saving locally, especially if there are many graphic elements. I really hate it when what could be a simple page loads a couple of megs flash, java, quicktime and whatnot.
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