MCM Electronics

Isolation Transformer / Ground Loop Isolator By Distributed By MCM (4170) MCM Part #33-8700

4.5 stars 5 reviews
MSRP: $24.95
You Save: $15.96 (64 %)
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Ground Loop Isolator
Transformer based isolator provides a high impedance isolation from AC power related ground current, preventing hum or buzz in sound systems and hum bars that appear on video monitors. Bi-directional device provides a transparent path for CATV and Antenna signals and is fully compatible with high speed internet and interactive digital cable boxes.

Specifications Top

  • 5MHz ~ 2.4GHz bandwidth
  • Compatible with all terrestrial antenna and cable television systems
  • Reduces or eliminates the effects of ground loops
  • Female "F" input and output connectors
  • Insulated metal housing
Note: This device will not pass DC power it should not be placed between amplified devices and power source, or between satellite receiver and dish.
Part Numbers
MCM Part #:33-8700
Distributed By MCM Part #:4170
Package Specifications & Dimensions
Weight:0.16 lbs.
Warranty:90 days
Need to Return?
Length:3.5 in.
Width:1.25 in.
Height:1.25 in.
Shipping Information
Extra Shipping Charge:No
Drop Ship:No

Product Reviews Top

  • by JAMESF52

    on 8/31/2015

    ground loop hum via Comcast

    Overall: 4 out of 5

    Greatly reduced hum in 7.5 channel system after Comcast claimed that it must be a problem with my equipment. It would be even easier to install this isolator if it had a male F connector on the set-top box side, instead of having to use a M-M coupler.

  • by Bullhead

    on 7/10/2012

    Cable TV Isolation Transformer

    Overall: 4 out of 5

    Excellent build quality and value. This item eliminated the ground loop issue I had from cable system. It would have been better if it had both male and female F connectors. Don't forget to pickup dual male F adaptor (or dual male F cable) if you will use this inline.

  • by DSmart

    on 4/23/2012

    Fixed DirecTV ground loop noise

    Overall: 4.5 out of 5

    The separate grounds to power receptacle(s) and the DTV antenna creates a ground loop. This can create hum in a grounded amplifier or sub woofer. The isolator fixed the ground loop when installed between the SWM power supply and the AV receiver*. The problem was not the SWM power supply as the problem was still there if the power supply was unplugged. If you have hum, disconnect the SWM-->receiver coax. If the hum stops, the problem is a ground loop. Note that if your DTV antenna is not grounded, there will not be a ground loop of this nature. * If you install between the SWM power supply and the antenna, there will not be any reception. WARNING: Do not use ground loop isolators for cable TV [CATV]! They do not have the bandwidth required and your DTV will malfunction. This MCM isolator seems to be the only product that has the required bandwidth.

  • by fredomax

    on 12/29/2011

    Works as advertised

    Overall: 5 out of 5

    I have an FM roof antenna connected to several radios and tuners throughout the house via RG-6 cable. One is a vintage 1970's receiver with a phono section which exhibited audible hum. I tracked the problem down to the FM antenna lead. When I disconnected it, the hum in the phono section went away. I ordered two of these Ground Loop Isolators. I connected one to the 300 ohm to 75 ohm FM antenna adapter on the back of the receiver and it solved the problem. I also have a stereo radio with an auxiliary output that shares double duty as an FM radio and computer speakers. The computer is hooked up to a cable tv modem. I was experiencing significant hum when I switched to the radio's auxiliary output. I added a Ground Loop Isolator there as well, and now the hum is gone. Bottom line is that this product significantly squelched hum in both of the applications in which I tried it.

  • by ronald.koenecke

    on 4/28/2011

    The Boater

    Overall: 5 out of 5

    Hi Guy's, While working on my on-board antenna system I noticed a ground fault voltage potential. This condition also reduced the quality of the shore based cable TV system channels. I also have an Galvanic Isolator (Ground Loop Isolator), connected to my shore power ground. I added the item below for the same reasons, to save my zinc's. Shore based cable TV system Isolation Transformer / Ground Loop Isolator This product solved the problem. Happy Channels

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