Baron’s Hobbies – Online Hobby Magazine » Trimersion Video Goggle Hack

Trimersion Video Goggle Hack

Posted on April 13, 2010 by aaronredbaron

If you have been interested in FPV (First Person Video) hobbies, but you don’t want to dump a huge bucket of coins on a decent pair of video goggles, you can hack your own from the unsuccessful Trimersion gaming goggles. Originally outrageously priced at $500, the Trimersion set probably never worked correctly for 90% of the few consumers who actually bought them. After a short time on the market the company went under and the units have been selling on sites like Ebay and Amazon.com for around $100. If you are comfortable with soldering and basic electronics you can hack your own Trimersion set for basic A/V operation. With 640 x 480 resolution these goggles are comparable to many of the ~$300 goggles on the market.

A thread popped up on one of the forums where people began hacking the goggles and re-wiring them for basic A/V operation. Out of the box the Trimersion has a head-tracking gyro (only works for gaming) and is wired to a plastic “shotgun” game controller which powers the set with 4 AA batteries. The gun/goggle set is wireless from a base station which plugs into the A/V signal and game console. Unfortunately this wireless video link is very poor and prone to interference from many common electronics (primarily WiFi). On the forum people began to hack into the goggles and discovered several methods to rewire the goggles. The onboard 2.4 gHz receiver can be used, but its not stellar quality. Most people prefer to simply add A/V connectors directly to the goggles, and wire them so they can be powered directly from a single cell LiPo.

While the original thread outlines several great modifications, its hard to sift through all the info to find what you need to do the hack. Here is the process I took.

1. Remove A/V connectors from Base station with a soldering iron and solder sucker and/or de-soldering braid.

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2. Flip the goggles over, remove the screws and take the unit apart.

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3. Very carefully use your fingernails to grab the small 6 pin connector going to the LCD board, and while holding the LCD board with your other hand, gently remove the connector.

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4. Remove the 3 screws holding the remaining circuit board, remove cable to gun, and disconnect the three connectors going to the bottom of the case for volume, brightness control, etc. The wires to the headphones will remain connected to the board for the remainder of the hack unless you want to change it to an in-ear bud or put a headphone jack in or something.

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5. Gently tape back the wire harness to expose the five solder pads holding the headtracking gyro in place. Remove the headtracking gyro with a solder sucker and/or de-soldering braid.

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6. You can remove the antenna, it serves no purpose laying down against the RF sheild as it comes from the factory. You can either just leave it off, or there are already provisions for making the RF part of the circuit work better than ever built right into the circuit board, but this only offers limited performance on 2.4 gHz. In a later article I will outline how to add a switch so you can use either A/V in or the built-in 2.4 gHz receiver.

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7. Find the connector where the cable to the gun plugged in and flip the board over, your power connectors will be added here, as well as a jumper to make the headtracker on/off switch function as your main power switch. On the last pin next to the 45′ angle on the board (we’ll call this pin 7), scratch off the green coating from the ground area just outside pin 7 with a hobby knife. Place a bead of solder between pin 7 and the ground for the jumper.

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8. Add your power wires, with plenty of lead length to work with. The positive goes to pin 1 and negative goes to pin 6 as shown.

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9. Add your A/V input wires as shown; brown is the common ground, orange is the video, and white and red are audio. I found servo wire to be perfect for this job.

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10. Cut off the yellow A/V connector from the group, and bend the tabs to arrange them together closely (be careful the tabs can’t short out). Break off the plastic tab where shown below to make room for the A/V connectors. Use the tabs to help find the spacing to drill holes for the A/V connectors.

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11. Drill holes for the A/V connectors and test fit them. Run the ground (negative) wire to the tab connected to the outside off all three AV connectors. Run the video to center of the yellow, and the red and white to the center of corresponding red and white audio connectors. Use hot glue to hold the connectors in place, being careful not to get any glue on the connectors where it would prevent contact.

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12. Put the unit back together, you can feed the power leads out where the gun cable used to come in, and use a grommet for a 50-90 sized helicopter canopy to make it look finished. Scratch off the “Tracker” lettering, the switch will now serve as the main on/off switch. Another option is to mount a small enough battery inside the goggles with a connector accessible behind the rubber shade flap. The goggles can be powered from any 3.3-5.0 volt source, so a single cell LiPo is perfect! It pulls about 350 mAh, so you could safely get a little over 2 hours from a 1000 mAh cell. If your head is too big to fit, just make one cut on one side of the head strap. I used a piece of velcro on the top of the head strap for my 2000 mAh single cell LiPo.