Ram Cradle Hardware Review

Ram-Mount is a company that has an earn reputation for making rugged mounting hardware for lots of electronic devices. This review is for their new line of PDA mounting cradles that include powering the PDA plus a serial connection for GPS use.

The Cradle

This review is based on the new PDA powered docking cradle for the iPAQ pocketpc for models 36xx, 37xx, 38xx, 39xx, 54xx, 55xx. I tested it on my iPAQ 3970 which is shown at the left with a memplug dual CF sleeve installed.

The picture on the right shows the bottom of the cradle where there is a connection to power the unit from a 12 V source via the barrel power connector shown in the image at the far right and it also provides a 9-pin D RS232 connector to be used to hook a peripheral up to the pocketpc serial port. This is where you would hook a GPS device if you have one that needs a serial port. You can use the same cable as you would use to hook the GPS to a pc.

The external power connector hooks to the supplied 12V power plug that connects to your vehicle battery. Two versions of the connector are supplied. One has a accessory plug outlet on it and the other is intended to be wired direct to the battery. Note that the connector to the cradle is the same size as the one that some of the iPAQ models use for their 5V input so you need to be careful not to plug it directly into the iPAQ. I suggest you mark the cable so that you can tell it apart. Inside the housing is a regulator to drop the voltage down to the correct 5 Volts for charging the iPAQ itself. Note that the power connection is not intended to power the GPS or other peripheral that could be connected to the serial port.

The top view shown at the right provides a view of the interface connector to the iPAQ and shows the depth of the unit. This cradle can accept any size expansion pack from the smallest, such as the dummy pack that has the screen cover to the largest pack with two ports and a battery pack installed. In addition the top only holds onto the PDA at the edges so any CF or SD devices can easily protrude from the end of the unit. There are even cutouts for headphone jacks and the stylus.

The clip at the top of the cradle is spring loaded with a heavy spring to provide a solid mount for the iPAQ by holding it down under pressure. Once the PDA is in place it isn't going anywhere until you decide to remove it. To install the PDA you should pull the top clip open far enough that the PDA can be inserted against the top clip. Then the PDA should be slid down to the bottom half of the cradle. This will prevent an damage to the interface connector that might be experienced if you try and install your PDA on that connector at an angle. To remove the PDA you should lift the entire PDA up to clear the lower cradle housing and then remove the PDA from the top clip. My wife wasn't particularly happy with trying to use this mount due to the weight of the spring.

Assembly details

Ram-mount makes many different cradles for PDA's and most are fully assembled when you get them. However, because this one supports so many different models Ram decided to send it in kit form. They include a manual on how to assemble the unit, but you can download a better color version from their web site (pdf). The picture below shows the kit assembled with the bottom cover removed. There are three small PC boards in the kit and several cables. I have a few modifications to the instructions listed below.

  1. Before starting, slide the cover onto the mount itself and get a feel for how much pressure it takes to assemble the two together. Then set the cover aside until step 5.
  2. In step one they tell you to pick one of two harnesses to install but offer no guidance as to which one you need. For all GPS use you need the Red hardness. The only time I can imagine needing the black harness is if you plan to hook directly to a laptop with this connector, or your cable already has null modem wiring.

  3. I found it easier to reverse steps 3 and 4 and I placed my iPAQ in the cradle to help hold the connector in place while doing the assembly. This offers the additional check of ensuring you have the right connector end and are holding the connector in exactly the right place.

  4. In Step 5 they suggest to snug down the screws until the unit is closed. I think this is a good way to pinch some wires. I suggest sliding the cover on the unit until it is tight against the cradle housing. If you encounter more resistance than when you did it originally then check for wires that may be poking out from under the cover. Once you get the cover on snugly it is easy to install the two screws with a phillips screwdriver.

Car Installation

The cradle, as purchased, does not come with any vehicle mounting kit. You will need to order this separately. You need one end to be the diamond shaped connector to interface properly with the cradle. It is mounted with two nuts and screws supplied with the mount. The other end will need to be whatever is needed to mount to the car, boat, motorcycle, etc. In between will be the double ball joint extension system that Ram-mount is so famous for. There is no guidance as to which ball system (A, B, C, or D) will work with this unit. I don't have the rest of system so I can't comment on how well it works installed in a vehicle but it should be just fine.


Ram-mount has designed a very rugged cradle that will hold the PDA well in place under spring tension. It can take a bit of effort to install and remove the PDA depending on where it is mounted in the vehicle, so be careful and expect to use both hands. Also be careful that you insert the PDA straight into the connector.

By: Dale DePriest

initial release 2004/1/19