FAQs about Signal Transmission

Q1. How do I transmit a signal received from an antenna to a building 200 feet away?

A1. First, you must convert the single-ended signal to a pair of differential signal (LVDS, RS-422, NECL, or LVPECL), because transmitting a weak, high-speed single-end signal over a distance over even 20 ft is not recommended.

The PRL-430AN-SMA, dual channel ECL receiver, is a product developed for NASA for this type of applications.

Q2. If my receiver in the other building has 124 Ω NECL inputs, what do I use?

A2. The PRL-432 has dual channel differential 50 Ω SMA ECL inputs and differential 124 Ω Triax outputs. Long distance transmission using the 124 Ω output is not recommended, because the shielded 124 Ω cable needed is costly and has lower bandwidth compared to those of standard 50 Ω cables.

Q3. If my recorder has 124 Ω NECL Triax outputs, how do I get back to 50 Ω NECL systems?

A3. The PRL-433N has dual channel 124 Ω Triax inputs and complementary 50 Ω SMA outputs. The PRL-432N has the reverse. The PRL-432 and PRL-433 are also products developed for NASA.

Q4. How do I drive multiple TTL loads over 100 ft away from a single TTL input?

A4. The PRL-414 is a 1:4 TTL fanout module that has been tested by the US Coast Guard for driving 100 ft long 50 Ω cables.

Q5. How do I convert a single-ended TTL signal to a pair of complementary TTL signal for driving long lines?

A5. The PRL-420TD is a dual channel single-ended TTL to complementary TTL converter.