Dual Purpose: Mallincam AND Wireless - HOW?
Posted 27 December 2007 - 08:18 AM
Posted 27 December 2007 - 09:59 AM
Posted 27 December 2007 - 10:22 AM
Operating these devices which require FCC licenses without being licensed is risking a lot of your hard earned cash and potentially even your freedom.
Can you get away with it? Maybe. Just like you can get away with speeding.
Will you get away with it? Maybe.
How would you get caught? IF the device you operate without a license on a frequency and at a power that requires one, chances are there's another entity who IS operating legally, with a licence - and possibly providing a service for which they are paid. If your operation interferes with them and they report you (which they probably would), you will probably get caught.
Think about it long and hard, is it worth the $10k (per offense) or even possible jail time? The FCC is not going to care why you're operating such a unit, or who you are, or that it's a hobby.
Posted 27 December 2007 - 11:10 AM
1. Is FCC certified
2. Has less than 50 mW of power
3. Provides good quality video transmission
4. Provides it over an acceptable range?
Posted 27 December 2007 - 01:33 PM
I will be trying my MPEG-2 system with my new 9" CRT and my 50" DLP TV, first with the wireless MPEG-2 and then hard wired with S-video, so I can compare the two.
Posted 27 December 2007 - 01:55 PM
Posted 27 December 2007 - 01:58 PM
I was not impressed and ended up returning it. I had to work a lot harder than I thought I should to get them aimed at each other for a clean transmission. I literally tinkered with it off and on for hours. Perhaps something was interfering? Once I got it right, things seemed fine, but it took quite a bit of tinerking and they were only about 8 feet apart. Lots of static, crackling, and popping to get to that point. I was testing with digital video cameras and my XBox. And considering I will be setting things up and taking them apart for some time, I didn't think I'd care to go through this with each and every viewing session. Very time consuming.
That's been my experience. YMMV. I'm sure I'll revisit wireless someday, because I also want to do serial bluetooth to the hand controller (which I have had success with on my Meade LXD-55 mount), but am content with the simplicity and clean signal of a cable for now.
Posted 27 December 2007 - 06:43 PM
Posted 27 December 2007 - 08:52 PM
Posted 27 December 2007 - 09:10 PM
How about a laptop at the scope with a wireless router. S-video into the laptop's video card. 802.11g wireless routers/cards have huge data transfer rates, hundreds of feet of transfer range, no FCC issues. You get a screen at the scope, the ability to drive the scope mount with a planetarium program and wireless video. Used laptops are no more expensive than some of the wireless video equipment being talked about.
great idea! Thinking outside the box.
Actually, IMHO, I think in this situation under many constraints, there is no need to stick with (digitally) "streaming video" or (in analog method) "broadcast/RF-transmitting video" concept.
Note in the high-sensitive mode, it is very similar with "slow scan TV (SSTV)" where there are just frequent new image update (e.g., every 2.1 second) while the rest of time, it is repeating the same thing at video rate. In such case, one can program a laptop to do TWAIN VGA-resolution capture every 2.1 (or 1) second. This will be the best quality capture and consume little bandwidth. The local laptop screen will change at almost the same update frequency as teh camera. The rest laptop and home PC WiFi link-up is just as described as Joe had said (using Microsoft RDP) or using VNC.
Posted 27 December 2007 - 10:18 PM
I did order a cable that works on the GSTAR-EX and is supposed to work on the Mallincam to control the camera settings via computer. I guess a motorized focuser is next on my wish list.
Not sure where you ordered the Mallincam cable from but the cable I ordered also came with the RS-485 to RS-232 cn=onvertor which you are going to need, since the interface to the Mallincam is RS-485. The big issue with my converter is it would not work with the Mallincan (or the GStar-EX) until I supplied it with external power (5~12 vdc) The other thing to remember is the software to drive the camera will only work on com port 1.
Since I have 2 cameras I built my own cable and ordered my own converter for the 2nd unit but was still hampered by the need to use com port 1. The solution was to use a serial port switch. While that setup worked it required the use of null modems between the serial port output connectors and the RS-232 to RS-485 converters.
Posted 28 December 2007 - 09:03 AM
Posted 28 December 2007 - 09:42 AM
www.marklessastronomics.com sells a PC stalk which attaches to the scopes rocker box (Newtonian Dob) and keeps the laptop moving around with the scope when it slews, but it presents balance issues for scopes under 18", with my 12.5" scope it was not possible to install the PC stalk so the laptop must sit to the side of the scope independently.
The biggest benefit to going with a wireless transmitter is that you don't have the cable wrapping around the scope as it slews around to various targets. A cable wrapped around the scope can do serious damage to equipment if your not careful, in the dark, it is hard to see when the cable is getting caught up and about to tug on equipment.
Posted 28 December 2007 - 09:43 AM
That is not the cable I ordered from GStar for use with my MallinCams. Mine is 10 meters in length and has an RS-232 connector to interface with the COM port on the laptop. It cost about $140 delivered to the US via global express mail. I just checked the GStar site and I could not fine the one I purchased.
The cable that I have does work with the MallinCam; however, you need to have the camera in 2.1 second mode when making menu changes via the software on your computer. So you will still need to have access to the camera to turn off the HYPER mode before you change the gain and other parameters.
If you want to control some of the HYPER functions via the GStar cable and software, that is a possibility. But you would loose the ability to use the "X4" function. This would limit you to a 14 second exposure. But you could chage from 2.1 seconds to 7 and to 14 using a computer. The camera would need to be sent back to Rock to have this conversion made.
When the wireless is released, all camera functions will be available through the remote.
Posted 28 December 2007 - 09:52 AM
Posted 28 December 2007 - 11:34 AM
Jack, thanks too for your helpful info. I knew that Rock was planning on retrofitting our cameras with the wireless option when he is ready, but I thought this option of the cable might work in the meantime. I really want the wireless function, and hope it will be available soon.
Posted 28 December 2007 - 12:12 PM
Posted 28 December 2007 - 12:20 PM
I can't say the cable won't work but I will say this:
The My Astro Shop guys have changed the cable they used to sell (the one I ordered from them was different));
AND they have either changed the interface that is used on the GStar-EX OR there is an error in their description of the cable on their website.
Here is part of the description for the cable you ordered:
"This 5 meter cable connects to GSTAR-EX cameras with RS232 interfaces and the RS-232 port D-Type of a computer."
Here is the description of the GStar interface from their current manual:
"Interface: 5 buttons for OSD control on back panel plus RS-485 interface for computer control"
Unless Rock has changed the interface, the Mallincam uses an RS-485 interface not a RS-232. Both my Mallincam and GStar-EX camera use a RS-485 interface not a RS-232 interface. As stated in another post these camera are based on other cameras. Those camera are available in RS-485, RS232 and RS422 flavors.
When I first got my Mallincam (model with only 7 and 14 sec integration switch) I contacted Rock and ask him about the serial interface because I wanted to control it remotely. He stated the interface was RS-232. Well after spending countless hours trying to make the camera work I figured out it was RS-485 not RS-232. I then ordered a cable from My Astro Shop that was used on their GStar-EX camera (which I also own) with a RS-485 interface. The cable worked on both.
I decided I wanted another cable but didn't want to spend the money for their 10meter cable which is all they sold then. So I built my own. The RS-485 converter which I mentioned in my earlier post was the same one that was used in the cable I purchased from My Astro Shop.
I am hoping that My Astro Shop didn't change the camera interface and just worded the cable description wrong. Because if they did switch, then unless Rock has switched to RS-232 interfaces that cable won't work.
Posted 28 December 2007 - 04:51 PM
I have had no issue with my devices in that frequency band and I don't have to worry about the devices operating near frequencies of microwave ovens. LOS operations on these devices at 100mw can be 800 to 1000 ft.
Posted 28 December 2007 - 05:38 PM
434 MHz is in the middle of the 70CM amateur radio band. Unless you are a licensed amateur operator you are operating illegally. And that is NOT UHF TV CH 59, but Cable CH 59.
Posted 28 December 2007 - 08:56 PM
With all due respect I suggest you go learn about the 434Mhz band before you publicly accuse me of operating illegally within it.
Posted 28 December 2007 - 09:28 PM
The Amateur Radio 70CM Band is: 420-450
[Code of Federal Regulations]
[Title 47, Volume 5]
[Revised as of October 1, 2006]
From the U.S. Government Printing Office via GPO Access
CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION (CONTINUED)
PART 97_AMATEUR RADIO SERVICE--Table of Contents
Subpart D_Technical Standards
Sec. 97.301 Authorized frequency bands.
The following transmitting frequency bands are available to an
amateur station located within 50 km of the Earth's surface, within the
specified ITU Region, and outside any area where the amateur service is
regulated by any authority other than the FCC.
(a) For a station having a control operator who has been granted a
Technician, Technician Plus, General, Advanced, or Amateur Extra Class
operator license or who holds a CEPT radio-amateur license or IARP of
Wavelength band ITU--Region 1 ITU--Region 2 ITU--Region 3 see Sec. 97.303
UHF MHz MHz MHz
70 cm......................... 430-440.......... 420-450.......... 420-450.......... (a), (b), (f).
And TV channel 14 is 470-476MHz. See this site.
You are operating in the amateur band - in an unauthorized manner - if you are on 434MHz.
434MHz is assigned to Amateur Radio Operators in all regions.
Posted 28 December 2007 - 10:22 PM
Posted 28 December 2007 - 11:32 PM
Read FCC part 15 on Radio Frequency Devices the exemptions are there. But if you think your correct I suggest you contact the FCC. I have already been down this road with another mis informed amateur radio operator in my neighborhood. He was a bit red faced when it was confirmed that my system in fact met one or more of the requirements in Part 15 and didn’t require a license to operate in the said frequency band.