What is this connector?

Nice photo (why don't mine look that good)?

This was discussed in the past. It's a test connector and is probably a I.PAX MS-156 connector, or a Hirose u-FL. I haven't had the time (or the interest) in trying to untangle which is which. My guess(tm) is that it's an MS-156.

Also see: If you're trying to use this connector to attach a permanent pigtail, I suggest you give up. The connector will not survive many insertion and removal cycles, and it not very strong. The RF switch located inside the connector is also kinda flimsy.

Thanks. Photo was taken with a Nikon CoolPix 995 that still has the best macro capability of any non-SLR camera. Shot in TIFF mode (no jpeg artifacts until after the edit.) Strobotron studio strobe system. One direct light, and two soft boxes. Lens stopped all the way down to get the depth of field. All the light the Strobotrons could make to enable the small lens opening.

You can get pretty much the same results with a soft light cave (look at B&H photo and other places) and a few cheap slave strobes. I use the little $16 Vivitar strobes from Walmart a lot. I put a photoslave on each and array as many as needed.

You can make your own soft cave with a few hoops of heavy steel wire and some white silk or ripstop nylon fabric. Take a look at the photos of the commercially made soft caves and make one of your own.

The insert photo was taken with the lens opening about 3/4" away from the connector. That's how good the Nikon macro is.

Sorry to have to ask an already-asked question but I'm rather new to the group and I didn't know enough to google the group archive.

Yes, I want to attach a permanent pigtail. I don't mind hacking the card and don't mind giving up the use of the internal patch antennae. I've looked at various sites addressing hacking other cards. My concern is whether the result will work RF wise with the diversity switch still in place and without any RF mods. I wonder if there are any software hacks for either card to turn one or both antennae off and on like there are for other cards?

The Netgear card works so well as it is that I might just try a hack to see what happens.

Thanks, John

Sigh. My comparatively cheap Canon A70 only goes down to about 30 mm and ends up with a 2mm depth of field. Closeups look terrible. Yours is MUCH better.

I have the bad habit of tearing things apart to see what's inside, taking a few pictures, and only then trying them out. I don't have any light cave, strobes, or even a camera tripod (it's being used as a temporary antenna mount). Thanks for the pointers. I guess that's what it takes to get decent closeups.

Wow. Ok, I'm impressed. $320 for referbished Coolpix 995. Well, that's what I just spend keeping my truck rolling. Maybe next month.

I would not bother with the U-FL connector and just solder on a cable. I suggest a 0.141 semi-rigid cable with an SMA connector attached. Be sure to get it with the connector attached as it's a serious effort doing it yourself. The semi-rigid cables outer jacket is easily solderable to a convenient ground. The real trick is to keep the exposed part of the center conductor (where it leaves the shield) as short as possible. I don't have either card handy so I can't suggest the exact location for the pigtail. Post a photo please (top and bottom).

You won't have any problem with the diversity switch located nearby. The card will find the proper antenna and leave the switch in the position of the best signal. The real trick is to find a location that's 50 ohms on the board. Most of the diversity switches run at a much higher impedance to reduce the effects of PIN diode conduction losses. When I do such butchery, I usually use a spectrum analyzer and directional coupler to make sure I'm getting the rated power and have a reasonably close to 50 ohm match.

There are usually tons of surplus semi-rigid cable and assemblies available surplus. Of course, when I need to find one, I can't find a thing. Googler's block, I guess.

This is kinda cute. How to may your own R-SMA connector for semi-rigid cable.

Good luck.

IF your camera will allow it, try the small f stop and massive light technique. That will give you the best possible depth of field. The Nikon only goes to f/9 in macro mode but that's enough to get the results shown.

I used the strobotrons because I had them set up for another shoot. You can get similar, maybe as good results using $100 worth of those Vivitar Wallyworld strobes I mentioned. Square law applies here too. Two strobes produce twice the light of one. Takes 4 to double it again. Fortunately they're so cheap that you can spread 'em around as you need 'em.

You can do essentially the same work with one big strobe and some reflectors and diffusers. I have the biggest strobe Nikon makes for on-camera use (SBX-90 I believe, without going to look). That thing makes so much light when set wide open that I can bounce it around with reflectors and get just about the same results as with multiple strobes.

The advantage of digital is, of course, you can look at your work as you shoot. When I'm working in my studio I keep a 12" color TV hooked to the Nikon's composite video out so that I can see the picture before and as I shoot. That's a huge help in getting rid of shadows and for knowing when you have the right shot. I didn't count but I imagine I still took something around 20 shots to get that insert photo lit and exposed just right.

I have the same habit. My staff is shocked into thinking I'm sick if I buy a new gadget and actually try it before taking it apart :-)

You'll need a couple of other things. Nikon has gone to a proprietary 3 pin barrel connector for flash connections. You'll need to get the Nikon proprietary to hot shoe cable. If you plan on using other brands of strobes you'll also need a voltage protector. The Nikon can only handle

50 volts on the sync lead. Many strobes output hundreds. I can't recall the URL off the top of my head but if you get the camera drop me a note and I'll look up where to get the voltage protector.

Photos are here:

BTW, these were taken quickie-style with the Nikon and the Nikon flash with a diffuser over the front (white towel), held off to the right a little to avoid glare. Not as good as the studio pix but OK.

I did microwave ham radio back in the 80s. I'm afraid that what little equipment I have left is woefully out of date. I do have some rigid coax/SMA connectors somewhere around here. That's a great idea.

Do you thing a good possibility that the test jack will be near 50 ohms? I read that Hirose info and it looks like the mating connectors are all 50 ohm. I can probably safely assume that the transmitter power is routed to the antenna with the test point? If my old HP microwave mw meter still works I can see for sure.

Thanks for the info and help.

BTW, I just got my new Proxim B/G gold card today. The software is rather primitive (having to look up the WEP key instead of typing in the passphrase like all the rest I have) but the receiver in particular, kicks ASS compared to the others I have. With the built-in antenna. Here in my recliner with a concrete, a stud wall and about 75 ft between me and the WAP, where the NetGear WG511T shows about -78dbm on receive and the SMC could barely stay connected, this one shows -48 and has the bargraph pegged. The card utility says that it has backed the transmitter down to

50mw for this link.

I can hardly wait 'til the pigtail comes in and I can try some external antennae.

John

20 shots? I usually do 2 or 3. I really like the TV monitor trick. I have a pair of cameras (Sony MVC FD-100, MVC FD-70) with cracked LCD displays. Methinks using the video output instead of fixing the display might be a cheap fix. I'll try TV on my closeup work. Good idea. Frankly, I've never bothered to read or study much about photography. I'm from the point-shoot-pray skool of impulsive photography.

Yep. I have to know how it works before I can abuse anything effectively.

My test equipment looks like a museum for 1970's RF junk. However, I have access to a modern lab if I can convince the management that I'm doing something useful or interesting.

Yes, 50 ohms. I goofed. Some cards transform the 50 ohms from the radio section to a higher impedance at the diversity switch to cut losses, and then back down again to the test point, or just leave the impedance high and drive a higher impedance antenna system. Neither of the cards shows do this. Looks like everything is 50 ohms. Sorry.

HP436A ? I got tired of blowing up the bolometer/diode heads and retired mine.

If you're going to attach a 0.141 semi-rigid cable, the way to do it is to notch the board ground up to the trace. Then solder the shield to BOTH sides of the board ground. Keep the coax to 50 ohm trace transition very very very very short. Another nice thing about the notch method is that it might be possible to replace the plastic cover (after drilling an exit hole for the coax). I'm not sure exactly where to make the connection. Also, before you attack, make sure there's no DC sitting on the antenna. You may need a coupling cazapitor if there's DC (from the diversity switch).

Actually, I like that better. There seems to be some problems with built in ASCII to Hex WEP key converters. Despite its simplicity, there is no guarantee that every manufacturer does it exactly the same way. With Hex, there's only one way to do it.

I really doubt that the card has 30dB better field strength sensitivity. Something else must be happening. -48dBm is also a VERY strong signal, far more than I would expect from a 75ft link through two walls. Back of envelope guess would be: Item Signal level 15dBm tx output +15dBm +2dBi antenna gain +17dbm -64dB path loss -47dBm -20dm wall attenuation -67dBm (or worse) 0dBi rx antenna gain -67dBm That's about 20dB shy of your -48dBm rx signal level. Something is wrong with the Proxim readings.