I purchased this device from a wal-mart here in maine. It worked like a champ first time out of the box, a really neat little device.
I bought it so that I could play mp3 audio through my van's existing sound system.
I have used it with a sony walkman cd player and with a usb flash drive. It worked fine both ways. However I did notice a bit of "device noise" when using the cd player.
Also , The manual that came with the device is wrong on at least two points:
First,  Contrary to the Specifications listed in the user instructions, the device will work with flash drives greater than 512mb. my pen drive is 1 gig and it works fine.
Second, The unit will also play back files encoded at greater than 128kb.although files
will begin to generate a bit of noise as the bit rate is pushed beyond 200 kb.However,
this could be a limitation of my van's sound system as opposed to a flaw in the modulator itself.
All in all, it is a terrific little gadget, well worth the $30 I paid for it.and considerably less expensive than replacing an entire stereo head unit .

(in reply to hoosier)

Hello new member here.  Im also curious about this unit too.  Has anyone tried hooking up an external hardrive that has a USB port?  More like those that house a 2.5 laptop hdd.  It says that it can handle any USB drive.

(in reply to dwoolsey90)

I purchased one of these devices and found it to be good. However, I changed cars and lost the list of radio station frequencies it will play over. Can you help me get another copy of this list, or post them?

(in reply to hoosier)

To view current Roadmaster VR3 FM Modulators (and to download most manuals for same), go to   http://www.roadmasterusa.com/fmmod_vr3.php

Radio frequencies for 1880 model are 87.7, 87.9, 88.1, 88.3, 88.5, 88.7 and 88.9 MHz

(in reply to fhsteacher)

Hey guys,
  I did not read all three pages of this post.  However, just in case it hasn't already been mentioned I would like to point out that the VR FM modulator isn't actually a modulator.  It is an FM transmitter. An FM modulator works by plugging into the antenna receptacle on the rear of the radio unit. A modulator outputs a signal that can be accepted directly by the FM receiver. 

(in reply to dwoolsey90)