That is correct.  There are no moving parts.

Phil.





----- Original Message ----- 
From: "Lloyd Rasmussen" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, May 02, 2010 2:12 PM
Subject: Re: ARB 740


> It is the ARB-704.  I have one between my FT-950 and the old Yaesu FL-2500
> sweep-tube amplifier I use.  Older amplifiers like this were keyed by a
> relay in the transmitter or transceiver that drove them.  Thus, if the 
> coil
> drew 100 milliamps or more, it was no big deal.  Also, if the voltage was 
> 50
> or 60 volts, the transceiver's relay could take it.
>
> Modern transceivers have a transistor at the keying connector, and expect
> lower voltages and currents to be keyed, as found in modern linear
> amplifiers.  I don't think this relay buffer contains additional relays, 
> but
> contains some more beefy transistors that can take what the linear 
> produces.
>
> In my case, if I drive my linear above a certain power level, the relay
> begins to trip out intermittently.  I haven't identified the cause yet. 
> It
> could be ground loops, RF on the keying line, or something else.
>
> Lloyd Rasmussen, Kensington, Maryland
> Home:  http://lras.home.sprynet.com
> Work:  http://www.loc.gov/nls
>
>> -----Original Message-----
>> From: For blind ham radio operators 
>> [mailto:[log in to unmask]]
>> On Behalf Of Phil Scovell
>> Sent: Sunday, May 02, 2010 12:36 AM
>> To: [log in to unmask]
>> Subject: ARB 740
>>
>> Are any of you Icom users, along with solid state amps, using the MFJ ARB
>> 704 between the transceiver and amp for voltage protection and the like?
>>
>> Phil.
>> [log in to unmask]
>> WWW.RedWhiteAndBlue.ORG
>