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Assembly o' a Portable Video Receivin' Ground Station

This article discusses some alternatives and tips for settin' up a ground station for receivin' down linked video broadcasts.

It is a follow up t' me article from last year that described t' construction o' a patch antenna for use in receivin' broadcasts. That antenna works well with t' BoosterVision mini-gear cam available online. An apparently similar broadcastin' camera and receiver has been seen on t' shelves o' WalMart at a price competitive with BoosterVision's.

Once you have purchased a wireless video broadcastin' camera and receiver, matey, thar still remains t' question o' what t' connect t' receiver to. In me first summer o' video flights I worked with a minimal budget while provin' t' myself t' reliability and quality o' t' signal received from t' onboard video camera.

T' ground system I first assembled on a budget was nay portable as much as it was luggable. Ya scallywag! T' typical broadcast video receiver outputs video and audio signals on separate RCA jacks. I purchased a standard household VHS VCR with RCA inputs for $5 at a garage sale. Avast, me proud beauty! I spent another $5 for a small black and white television with RCA jacks at a Thrift Store. T' power t' VCR I purchased a Power Inverter that converts 12VDC t' 120VAC. Begad! This was originally t' be plugged into a car's power socket. Knowin' that I wouldn't always be near me car, I purchased a small, sealed 12VDC car booster battery. T' video receiver and television could be run directly from 12VDC, but since I already had t' Power Inverter, I used t' "wallwwart" powersupplies t' power all t' equipment from a single switched power strip. Begad!

This system be inexpensive enough, costin' less than t' BoosterVision camera, but it required a large tub t' carry it all, me bucko, and a protected area t' set it up. One o' t' downsides was that I could nay confirm t' quality o' broadcast signal while powerin' up t' camera at t' launch pad. Blimey! I would need t' enlist a volunteer t' monitor t' receiver, or scurry back t' it t' see if t' onboard camera was broadcastin' clearly. Well, blow me down! Another problem was that I needed t' either start t' recorder early, or stay near it t' start it when me camera's turn for launch came up.

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After refinin' me strap on camera pod system, me hearties, I was satisfied with t' quality o' captured video. Well, blow me down! T' time came t' refine t' ground station t' make it easier t' use. Well, blow me down! I decided that a camcorder capable o' recordin' t' video signal was t' way t' go.

RocketI researched CamCorders, assemblin' a list o' models that supported "line in". That capability is what enables t' CamCorder t' record data from an outside source. T' new ones that had it were all relatively expensive, costin' several hundred dollars for basic models. It seems that fewer and fewer models are supportin' external source recording. Avast, me proud beauty! I looked in a slightly different class o' electronics and came across me answer, t' Aiptek MPVR. It is a solid state media player and video recorder. It can serve as a digital video camcorder, 3MP digital camera, ya bilge rat, digital video recorder, audio recorder, mp3 player and USB harddrive. Well, blow me down! I purchased mine for $150 from CircuitCity, but they are widely available from other sources for slightly less. As with all things digital, arrr, t' price falls off smartly as follow-up models reach t' market.

Of particular interest t' me were t' MPVR capabilities as a digital video recorder, aka DVR. T' video from external sources can be captured as 640x480x30fps t' an SD memory card. T' videos are Mpeg4 encoded. T' built in 2.4" color LCD can be used t' monitor and play back recordings. Aye aye! T' built in speaker or earphone jack can be used t' monitor audio. Arrr! As can be seen in t' attached photos, ya bilge rat, t' MPVR is actually smaller than t' BoosterVision video receiver. It is powered by rechargeable Lithium Ion batteries that are compatible with some models o' Sanyo cellphones. Ahoy!

T' final step in makin' me receivin' ground station portable was obtainin' a small 12VDC power source for t' receiver. I took t' low-tech, and low capacity route o' usin' 8 rechargeable Lithium Ion AA batteries in a battery holder purchased at RadioShack. I needed t' solder a suitable power connector t' a 9V battery clip t' connect t' battery pack t' t' receiver. Ahoy!

With t' new, fully portable receivin' and recordin' station I can hold t' system in one hand, carry it t' t' pad, matey, and review t' quality o' t' camera broadcast as t' rocket is bein' prepped. I can then loiter on t' flight line, shiver me timbers, far from me car, and monitor t' camera signal. Ya scallywag! Just prior t' launch I press t' record button, shiver me timbers, and am able t' wander off in search o' me rocket while still carryin' t' receivin' station. When I'm nay receivin' video from t' broadcastin' camera, I can disconnect t' cable and use t' MPVR as either a standard camcorder or digital camera.

Since I have a digital camera, camcorder, audio recorder, and video recorder in me hand, matey, I can fully document t' flight from prep t' t' walk back in after recovery.

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To help ruggedize me newly portable patch antenna, ya bilge rat, I sandwiched it betwixt t' plastic lids from two inexpensive grub storage containers. Avast! T' container lids still snap onto t' container that is large enough t' hold t' receiver for storage. I even went as far as craftin' a tripod mount on t' receiver, and mountin' a bolt on a hardhat. Avast, me proud beauty! In times o' great need I could mount t' receiver on t' hardhat, me bucko, thus freein' me hands while t' recorder is running. Blimey! I’m nay sure t' world is ready for that fashion statement, arrr, so don’t hold your breathe waitin' t' see any pictures o' that configuration in use.

For longer trips, there’s always t' issue o' how long batteries will last. I have nay exhausted either t' MPVR battery, nor t' 8AA power pack in a casual day’s shooting. I know that t' 1GB SD card I use with t' MPVR can record 40 minutes o' nonstop video.

There is some additional support equipment that I brin' on long trips. Avast! I pack an extra set o' 8 AA batteries and a charger t' charge them. I also pack a spare battery for t' MPVR and t' charger t' charge it. Each charger can work from 110AC, or 12VDC, ya bilge rat, so I still pack that sealed car booster battery. T' point t' remember is that this is backup equipment, matey, and is nay needed for a day’s tapin' at a launch. T' MPVR also comes with cables t' connect t' recorder either t' a laptop, matey, or t' video inputs o' a recorder or large screen. Blimey! What better way t' review t' day’s launch festivities, than t' play back t' pictures, ground based movies, and downlinked videos in t' hotel lounge? While you’re thar with t' MPVR, ya bilge rat, you can take some more pictures o' your fellow fliers enjoyin' t' Apres Flight

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Contributed by Scott Turnbull

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