i want to create a female to female HDMI extender. i used 2 of this breakout board female HDMI socket (here) connected both of them with jumper wires and checked each wire with multi meter. connections seem good and there is no sign of short circuit. but when i use HDMI cables i don't get any connection.

any chance that jumper wire material is the problem ? should i be using some kind of special wires ? jumper wires are made of copper. i wonder what might be wrong ?

any ideas ?

EDIT : what i made


closed as unclear what you're asking by winny, Nick Alexeev Sep 4 '17 at 22:57

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • 1
    \$\begingroup\$ Welcome to EE.SE, but please capitalise and punctuate properly for legibility and credibility. You have no datasheet link for the socket so we can't guess its intended application. HDMI uses radio frequencies and the cables internally are screened and impedance matched. You have created a discontinuity and probably an array of antennae radiating signals. \$\endgroup\$ – Transistor Sep 3 '17 at 13:08
  • \$\begingroup\$ @Transistor thanks for the advice. sorry i am new to this community. what can i do to make this right ? any ideas ? \$\endgroup\$ – KababChi Sep 3 '17 at 13:10
  • 2
    \$\begingroup\$ @KababChi - Start by paying attention. Transistor suggested that you capitalize, and your comment ignored his suggestion. Edit your post using the Shift key on your keyboard. Since you found a picture of your adapter, provide a link to the datasheet. On a more substantive note, learn about transmission lines and impedance matching. You may (but probably won't) get better results if you identify signal pairs and replace your wires with twisted pairs. HDMI works at very high frequencies, and is very picky about its transmission medium. In other words, pay attention to what he wrote. \$\endgroup\$ – WhatRoughBeast Sep 3 '17 at 13:33

but when i use HDMI cables i don't get any connection

HDMI uses high-speed connections, this requires high-frequency signals. To maintain signal integrity (keep the signal as it should be, not distort it) these signals need to be transported over a proper transmission lines. The HDMI cables are constructed such (small coaxial/shielded cables) that they are proper transmission lines for these signals. Your breakout connector and wires are not proper transmission lines for these signals.

So what happens is that your "contraption" causes reflection and attenuation of the HDMI signals. The electronics at both ends of the HDMI cables try to setup a connection but fail because the signals get distorted too much.

Usually you might sometimes get away with cutting open an HDMI cable, separating the wires and then making the connections you need, provided you keep everything small so that the "disturbed" section of the HDMI cable is as short as possible. But even then, no guarantees.


Even if it did work, is it not easier(and probably cheaper) to just buy female-female Adapter?

e.g.: Postta HDMI Adapter

this is the first thing, that comes up on amazon.

  • \$\begingroup\$ i know these extenders and couplers exist. my purpose is to connect the 5v wire to a relay so i can control it. its not just an extender. sorry i should have mentioned in the main post. but first i need to get this to work. \$\endgroup\$ – KababChi Sep 3 '17 at 13:27
  • \$\begingroup\$ So you can control what? The HDMI signals? You can't switch HDMI signals through a relay. \$\endgroup\$ – Transistor Sep 3 '17 at 14:47
  • \$\begingroup\$ @Transistor No. I want to switch on or off the 5v voltage. \$\endgroup\$ – KababChi Sep 4 '17 at 4:35

Not the answer you're looking for? Browse other questions tagged or ask your own question.