MCS2000 amp draw when off.

[N4KVE]

I use my MCS2000 with pin 4 & 9 jumped in the acc connector. This way no ign trigger is necessary. But when I do this, & the radio is off, is there a tiny draw of current? Thanks. GARY N4KVE

[Bill_G]

Put an ammeter in line, and measure it.

[N4KVE]

Put an ammeter in line, and measure it.

Thanks Bill, but I don't have the radio yet. I'll be getting it in about a week, so I have nothing to measure. However, I want to have all the wiring done in my car so I can just pop it in. Depending on the draw when the radio is off [if there is a draw] will affect how I wire it up. I don't need exact spec's, just to know if the car can sit a day or two w/o killing the battery. Thanks for any help. GARY N4KVE

[fineshot1]

Not sure of the pin 4 & 9 thing - never heard of that one for powering
up the radio but if you use the pin 15 ignition sense and main power
lead hot you should have no problems, or just hook up the main power
lead to an ignition power source capable of 15 or 20 amps.

[nrembis]

or just hook up the main power
lead to an ignition power source capable of 15 or 20 amps.

Depends on if high power unit or not(OP didnt say)....MCS2k 110w high power units draw 27-30 amps on Tx so 15amp circuit wouldnt cut it

[Will]

Main power lead goes to the battery due to the high draw on TX.

The IGN can go to the IGN/ACCY or direct to the battery. A 2 amp fuse is needed here to protect the control head circuits.

[N4KVE]

Main power lead goes to the battery due to the high draw on TX.

The IGN can go to the IGN/ACCY or direct to the battery. A 2 amp fuse is needed here to protect the control head circuits.

My UHF radio has no ign wire coming from the acc connector. However, it does have a jumper from pin 4 to pin 9 which I'm told negates the need for the ign wire. But I've heard this setup has a slight draw when the radio is off. So I use a switch between the car battery & the radio on the main wire to turn the radio on, & off. GARY N4KVE

[N6LAU]

My UHF radio has no ign wire coming from the acc connector. However, it does have a jumper from pin 4 to pin 9 which I'm told negates the need for the ign wire. But I've heard this setup has a slight draw when the radio is off. So I use a switch between the car battery & the radio on the main wire to turn the radio on, & off. GARY N4KVE

As far as I understand it jumping pin 4 to pin 9 simply prevents the radio from thinking an external emergency switch has been pushed while the radio was off and avoids a FAIL 01/79 on power up.

Joe

[wavetar]

My UHF radio has no ign wire coming from the acc connector. However, it does have a jumper from pin 4 to pin 9 which I'm told negates the need for the ign wire. But I've heard this setup has a slight draw when the radio is off. So I use a switch between the car battery & the radio on the main wire to turn the radio on, & off. GARY N4KVE

As far as I understand it jumping pin 4 to pin 9 simply prevents the radio from thinking an external emergency switch has been pushed while the radio was off and avoids a FAIL 01/79 on power up.

Joe

Confirmed, the 4-to-9 jumper is always in place, right from the factory, as well as the 2-to-3 jumper to enable the internal speaker. Early firmware versions of the MCS would not turn on when power was applied only to the main connector. Later versions seem to...I don't know what the cut-off was.

As far as current draw, yes, since the MCS doesn't use a hard switch for on/off, there will always be a slight draw when connected to main power. However, this is true even if the ignition sense lead is used to control on/off. It's very minuscule, and shouldn't cause any issue with the car battery.

[N4KVE]

My UHF radio has no ign wire coming from the acc connector. However, it does have a jumper from pin 4 to pin 9 which I'm told negates the need for the ign wire. But I've heard this setup has a slight draw when the radio is off. So I use a switch between the car battery & the radio on the main wire to turn the radio on, & off. GARY N4KVE

As far as I understand it jumping pin 4 to pin 9 simply prevents the radio from thinking an external emergency switch has been pushed while the radio was off and avoids a FAIL 01/79 on power up.

Joe

As far as current draw, yes, since the MCS doesn't use a hard switch for on/off, there will always be a slight draw when connected to main power. However, this is true even if the ignition sense lead is used to control on/off. It's very minuscule, and shouldn't cause any issue with the car battery.

This is the answer. Thanks. GARY N4KVE