I don't recall the mfj number, but it is exactly the same box.  I have 
two of them.  I did eventually get one from vectronics, but took a long 
time.  It really works great for tuning my screw driver.  It bypasses 
itself if you forget and leave it on, but I've only done that once or 
twice.  The real advantage with this type is you just leave it in line, 
couldn't do that with the palamars or the other one I use to have.
73
Butch
WA0VJR
Node 3148
Wallace, ks.


On Fri, 
9 Aug 2013, Bob, K8LR wrote:

> Hi Jim,
>
> I use a Vectronics vec512 noise bridge all of the time and it works GREAT!
> Unfortunately, it is currently out of stock and I don't know if Vectronics
> which is now part of MFJ will make any more units.  The VEC512 has two
> advantages over any other noise bridge.  First, you can keep it in line
> while you transmit as the unit has a relay that bypasses the noise bridge
> when the bridge is offas you can run up to 300 watts through it.  Therefore,
> I have my noise bridge hooked between my transceiver and my amplifier rather
> than after the amp.
>
> The second advantage is that the bridge is set to 50 ohms and when you null
> out the pulsing hissing noise with an antenna tuner in your receiver, you'll
> have a 1-1 swr all of the time unless you can't get a deep null.
>
> Bob, K8LR, [log in to unmask]
>
> ----- Original Message -----
> From: "Jim Gammon" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Friday, August 09, 2013 4:26 PM
> Subject: Experience with Noise Bridges?
>
>
> Not to be confused with LLOYD or Jeff Bridges.  I  am wondering
> if anyone on the list owns or has worked with a noise bridge? I
> would like to know how useful, and accessible they are and their
> capabilities in determining resonance points for antennas.
> Thanks and 73, Jim WA6EKS
>
>