icom&ameritron

[Cable Guy]

If you apply drive before switching the relay it's more wear on the contacts, Ideally it is better to open/close them when they are not carrying rf.


73
Jeff

Never had a ham amp and I always wondered which to key first, the transmitter or the amp.

 

[nomadradio]

If the receive-side contacts open up with RF energy still on them, you will draw an arc across the gap as it widens. Wears out the receive-side contact points prematurely. The end user will describe this as "the relay sticks" when he unkeys. Has to click it a couple of times to get the receive to come back. No, it's not "sticking", he just wore it out in a hurry.

Had a customer that was diabetic years ago. Used a home (garage)-brew box with four 3-500Z tubes. Insisted on using a foot switch. He would lose feeling in the foot on his foot switch and it would slip off. When he looked over at the wattmeter he would panic and SLAP the foot switch while still keyed up on AM. He woud be back about once a year for a new antenna relay in that box. Offered to put a keying relay in his base radio on my nickel, but he just liked his foot switch and turned me down.

People want what they want.

73

 

[SuperLid]

If the receive-side contacts open up with RF energy still on them, you will draw an arc across the gap as it widens. Wears out the receive-side contact points prematurely. The end user will describe this as "the relay sticks" when he unkeys. Has to click it a couple of times to get the receive to come back. No, it's not "sticking", he just wore it out in a hurry.

Had a customer that was diabetic years ago. Used a home (garage)-brew box with four 3-500Z tubes. Insisted on using a foot switch. He would lose feeling in the foot on his foot switch and it would slip off. When he looked over at the wattmeter he would panic and SLAP the foot switch while still keyed up on AM. He woud be back about once a year for a new antenna relay in that box. Offered to put a keying relay in his base radio on my nickel, but he just liked his foot switch and turned me down.

People want what they want.

73

Should have built him a sequencer

 

[Alexis Mercado]

@nomadradio

"Since 2018, I have activated the amplifier in that way, but I will still follow your advice to first turn on the amplifier with the foot switch."