Anytone AT-6666 RF Power

[Eldorado828]

Looks like he would be better suited with say an at-5555n that does the specs he's after. Jmo

 

[Greg T]

Looks like he would be better suited with say an at-5555n that does the specs he's after. Jmo

I did mention that to him a few weeks ago. He said he did some research and is afraid of the computer programming. I haven't researched it much, but I would think that radio would be nearly ready to use box-stock, no?

Some, not all, but some of these old schoolers are just afraid of new technology. They'd rather have a knob than a menu.

 

[Eldorado828]

I did mention that to him a few weeks ago. He said he did some research and is afraid of the computer programming. I haven't researched it much, but I would think that radio would be nearly ready to use box-stock, no?

Some, not all, but some of these old schoolers are just afraid of new technology. They'd rather have a knob than a menu.

As far as programming, neither require programming unless you want to customize settings. They're both cpu driven so there's no difference as far as that part goes. Now the cosmetics and power differ but yes the 5555N is around the specs he's after. Keep in mind there are 2 different 5555's, the at-5555 which is the same as Bob's quad 5 and then there's the 5555N which is like the crt superstar 7900. Both have similar specs and have great reports.

I only bring those up because they seem to better fit his application.

Although, I'm dancing with possibly getting the 5555N myself. The price is nice.

 

[Greg T]

As far as programming, neither require programming unless you want to customize settings. They're both cpu driven so there's no difference as far as that part goes. Now the cosmetics and power differ but yes the 5555N is around the specs he's after. Keep in mind there are 2 different 5555's, the at-5555 which is the same as Bob's quad 5 and then there's the 5555N which is like the crt superstar 7900. Both have similar specs and have great reports.

I only bring those up because they seem to better fit his application.

Although, I'm dancing with possibly getting the 5555N myself. The price is nice.

I'll check the two out and send him the info. He's in driver's hell right now with economy as such, and can't wait to permanently leave the cab.
I wasn't even aware of there being two, and i'll bet he isn't either. We'll see what he says! Thanx!

 

[Allen B]

I have a 6666 and I am almost certain that when I first bought it and had it on the meter, the RF power knob does in AM/FM mode turn the carrier down to 2 watts. In SSB it will limit the peak power. I don't remember what it was exactly but I believe it went under 20 watts PEP on sideband. I'll check it again if nobody else gets one on a meter first.

 

[Greg T]

I have a 6666 and I am almost certain that when I first bought it and had it on the meter, the RF power knob does in AM/FM mode turn the carrier down to 2 watts. In SSB it will limit the peak power. I don't remember what it was exactly but I believe it went under 20 watts PEP on sideband. I'll check it again if nobody else gets one on a meter first.

My cuz would like this radio but to run his amp he would need to be about 15 at the very most.

 

[Handy Andy]

his amp he would need to be about 15 at the very most.

Even disconnecting the extra Final in it, would not help here-still too much "dynamic range" that's due to the radios own "performance curve" and the pre-set limits the parts and their values used in it - already are expecting a "given range of power levels" (ALC/AMC/AVC/CVS/CNN/TNT/NBC/CBS/ABC - stull like that) - Like using a 4-cylinder where a V-6 used to be - power is less, so it wouldn't hurt in gas mileage, but will kill a transmission trying to pull a trailer. So, the AT-6666 can run, say a simple 4-pill drivin' straight on up to a 16-pill, but any amp with a simple preamp or even a 2-pill - the MOSFET drive level can still kill it. The PEP the thing can generate is what kills the Base/Gates of the next stage of an Amp unless it's protected or somehow attenuated (no - not detuned - resistive padding think Memory foam action only at room temperature )

The better way to go is to use less power - period. The AT-6666 for its' features, many like it, while others curse it.

I'd hate to think that he'd base is sole-operational deployment on the fact that it's a small footprint radio and sounds big. I have to give him credit for that - the PC-122 or a 146GTL audio wise -their effects are similar - and simpler the better. But the 4x6 from Anytone will kill smaller amps - that's the bigger problem.

Now if he's smarter at the approach - then he'd do up the station to run direct from the Anytone as he wishes then would install and establish the amp side by not worrying about the Anytone at all, and try to find methods to attenuate the 6x4's signal going into the amp, past it's input relay, with resistive network to dissipate the power the Antyone will produce

Now there are a couple of methods - including padding the input signal with a dummy load ACROSS the input of the amp - and let the Amp sip power as it needs from the network. This has to be done in a fashion that let's the amp see enough power (so you don't need a 50Ω - maybe more like a 150Ω or 75ΩΩ load network) to the input of the amp - this helps the amps own RF-sense see enough power but not kill it when the guys' screaming for skip and his buds to answer.

Now before the thread erupts into flames again, Let's do some math to help the user out.

Firstly - figure out how much of an SWR impact the amp and LOAD input expected is then place a value that helps you offset the parallel side of Ohms Law.

​

• The above is a DEMONSTRATION of possible outcomes using two different ohmic intents
• 150Ω is 3x 50Ω ohm - while 75Ω is only 1,5x 50Ω ohm
• Because of the power distribution (Think Divider)
  • - the 75Ω ohm load is able to handle nearly 3x the dynamics but has the higher losses in attenuation we are not discussing dB's here - although this could be shown as such.

So, others know, I've had to do some wrangling with setups using dummy loaded T-fitting (some have even used coaxial Stubs) to offset a power drive - and of course the SWR issues do come up. But to help you know more- the ohmic resistance added affects all, not just frequency - so this concept will help when you use multi-band setups to balance or offset a SWR spike that shows up in a band trap or otherwise both sides of the bandwidth ends, and the losses incurred when you reach the band spreads' end.

IF you were to try and attenuate-retune the input of the amp for the dynamics - sure you can change the internals and the amps own innards network to reduce the drive, but that does little for those that might want to save the amp to use in a typical mobile without having to drag along the AT-6666 and use say, a Cobra 29 for the mobile - now we have another condition, not enough signal can arrive to even power the amp to even key it if he uses RF sense.

So' it's why I'm only discussing one type of approach
- using resistive to attenuate the signal dynamics
​

• Else we are then trying figure out how much ALC and AMC changes have to be done
• In compensating what the High-Drive side of life the AT-6666 will produce

Unless he's wanting to use two AT-6666's in that scenario, 1 - for mobile and 1 - for Base - then he's just fine - but still has to run the amp that same way with both - then; when it came to sell - we don't lose the Farm over it

Only if we find more of a way to offset the power loading. Doing this Externally, instead of having to trick out the amp

We could trick out the amp just past the "sense cap" with a swamping resistor - but still that is an awful lot of power playing out in there - it can still cause problems.

So, I'm throwing this back at you and see if you can come up with some ideas we can use...

 

[Greg T]

Even disconnecting the extra Final in it, would not help here-still too much "dynamic range" that's due to the radios own "performance curve" and the pre-set limits the parts and their values used in it - already are expecting a "given range of power levels" (ALC/AMC/AVC/CVS/CNN/TNT/NBC/CBS/ABC - stull like that) - Like using a 4-cylinder where a V-6 used to be - power is less, so it wouldn't hurt in gas mileage, but will kill a transmission trying to pull a trailer. So, the AT-6666 can run, say a simple 4-pill drivin' straight on up to a 16-pill, but any amp with a simple preamp or even a 2-pill - the MOSFET drive level can still kill it. The PEP the thing can generate is what kills the Base/Gates of the next stage of an Amp unless it's protected or somehow attenuated (no - not detuned - resistive padding think Memory foam action only at room temperature )

The better way to go is to use less power - period. The AT-6666 for its' features, many like it, while others curse it.

I'd hate to think that he'd base is sole-operational deployment on the fact that it's a small footprint radio and sounds big. I have to give him credit for that - the PC-122 or a 146GTL audio wise -their effects are similar - and simpler the better. But the 4x6 from Anytone will kill smaller amps - that's the bigger problem.

Now if he's smarter at the approach - then he'd do up the station to run direct from the Anytone as he wishes then would install and establish the amp side by not worrying about the Anytone at all, and try to find methods to attenuate the 6x4's signal going into the amp, past it's input relay, with resistive network to dissipate the power the Antyone will produce

Now there are a couple of methods - including padding the input signal with a dummy load ACROSS the input of the amp - and let the Amp sip power as it needs from the network. This has to be done in a fashion that let's the amp see enough power (so you don't need a 50Ω - maybe more like a 150Ω or 75ΩΩ load network) to the input of the amp - this helps the amps own RF-sense see enough power but not kill it when the guys' screaming for skip and his buds to answer.

Now before the thread erupts into flames again, Let's do some math to help the user out.

Firstly - figure out how much of an SWR impact the amp and LOAD input expected is then place a value that helps you offset the parallel side of Ohms Law.

View attachment 49653
View attachment 49651​

• The above is a DEMONSTRATION of possible outcomes using two different ohmic intents
• 150Ω is 3x 50Ω ohm - while 75Ω is only 1,5x 50Ω ohm
• Because of the power distribution (Think Divider)
  • - the 75Ω ohm load is able to handle nearly 3x the dynamics but has the higher losses in attenuation we are not discussing dB's here - although this could be shown as such.

So, others know, I've had to do some wrangling with setups using dummy loaded T-fitting (some have even used coaxial Stubs) to offset a power drive - and of course the SWR issues do come up. But to help you know more- the ohmic resistance added affects all, not just frequency - so this concept will help when you use multi-band setups to balance or offset a SWR spike that shows up in a band trap or otherwise both sides of the bandwidth ends, and the losses incurred when you reach the band spreads' end.

IF you were to try and attenuate-retune the input of the amp for the dynamics - sure you can change the internals and the amps own innards network to reduce the drive, but that does little for those that might want to save the amp to use in a typical mobile without having to drag along the AT-6666 and use say, a Cobra 29 for the mobile - now we have another condition, not enough signal can arrive to even power the amp to even key it if he uses RF sense.

View attachment 49650
So' it's why I'm only discussing one type of approach
- using resistive to attenuate the signal dynamics
​

• Else we are then trying figure out how much ALC and AMC changes have to be done
• In compensating what the High-Drive side of life the AT-6666 will produce

Unless he's wanting to use two AT-6666's in that scenario, 1 - for mobile and 1 - for Base - then he's just fine - but still has to run the amp that same way with both - then; when it came to sell - we don't lose the Farm over it i

Only f we find more of a way to offset the power loading. Doing this Externally, instead of having to trick out the amp

We could trick out the amp just past the "sense cap" with a swamping resistor - but still that is an awful lot of power playing out in there - it can still cause problems.

So, I'm throwing this back at you and see if you can come up with some ideas we can use...

This is all excellent info and I greatly appreciate the efforts. I think his first mistake was buying the KL-503 simply because he "got a good deal". This is the first time I've ever seen someone buy an amp and THEN match a radio to it! LOL, but, you have to know my cousin. . The problem is all he knows is what he wants. He has no idea how to reach the desired goal. My idea is simple. I think he should sell the amp, pick out the radio he wants and will be happy with, and then go from there. He knows he will NEVER use the amp on AM. That simplifies things a bit. I'm thinking just buy the damn radio, IF that is the one he wants, and then look for a DX-500V or similar amp. I'm driving my 500V with my Yaesu FT-990, giving it 35 to 40 pep and she runs like the wind. It just seems logical to me that he would pick the radio he wants, since, this is where the interaction is. Then, to run the amp he simply needs to crank the RF power fully counter-clockwise and hit the power button on the amp.

 

[Handy Andy]

Ok, the reason why I mentioned the resistive part was to avoid another condition of that "What If" in the OF WHERE you place the attenuator.

One thing that many don't think thru on, is when you install the resistor network used to absorb all this "extra power" - is where you place this "shock absorber" (The Lemon Car example) Because if you place the shock absorber in the wrong place, it will fail faster than to deal with just springs alone - because the energy from the shock has to travel thru both but if one isn't up to the task - you'll potentially (SIC) get stranded

So, think of where the Relay is in the RF power line and what it will have to "absorb" on top of the expected range of power it is DESIGNED to take in.

The AT-6666 can easily get close to 50 watts. That KL relay is pretty small and can get overloaded from the input PEP power being sent thru it (think arcing and smaller AWG wire - Fuses).is close to 100VDC and maybe 0.5Amp DC current - have him think this thru - because the AT-6666 on its own can produce similar outputs the KL-503 could produce if you only used a smaller radio to drive the 503.

If you place the Resistors in BEFORE that amps' Relay - it stands a better chance to hold in and work thru its life cycle. Meaning; it lasts longer because of the amount of power it doesn't has to pass across the relay contact - just to get to the Resistor to get dissipated.

So, in reciprocal - yes, you have a resistive event loss in the coax, but it will have less effects of losses on the Receive because the '503 can compensate for this loss - even if you wanted to use it. (Pre amp)

Why?

Expected impedance...

You can expect to drop power across a resistive load at V x I - Rates - but remember the input receive is HIGH IMPEDANCE - meaning it's capable of listening for weaker signals (Hardly places any load on the antenna terminals) - so the 150Ω or 75Ω or even 300Ω load resistors are not going to sap all that much out of the RF budget for the Receiver to work with.

 

[Greg T]

Ok, the reason why I mentioned the resistive part was to avoid another condition of that "What If" in the OF WHERE you place the attenuator.

One thing that many don't think thru on, is when you install the resistor network used to absorb all this "extra power" - is where you place this "shock absorber" (The Lemon Car example) Because if you place the shock absorber in the wrong place, it will fail faster than to deal with just springs alone - because the energy from the shock has to travel thru both but if one isn't up to the task - you'll potentially (SIC) get stranded

So, think of where the Relay is in the RF power line and what it will have to "absorb" on top of the expected range of power it is DESIGNED to take in.

The AT-6666 can easily get close to 50 watts. That KL relay is pretty small and can get overloaded from the input PEP power being sent thru it (think arcing and smaller AWG wire - Fuses).is close to 100VDC and maybe 0.5Amp DC current - have him think this thru - because the AT-6666 on its own can produce similar outputs the KL-503 could produce if you only used a smaller radio to drive the 503.

If you place the Resistors in BEFORE that amps' Relay - it stands a better chance to hold in and work thru its life cycle. Meaning; it lasts longer because of the amount of power it doesn't has to pass across the relay contact - just to get to the Resistor to get dissipated.

So, in reciprocal - yes, you have a resistive event loss in the coax, but it will have less effects of losses on the Receive because the '503 can compensate for this loss - even if you wanted to use it. (Pre amp)

Why?

Expected impedance...

You can expect to drop power across a resistive load at V x I - Rates - but remember the input receive is HIGH IMPEDANCE - meaning it's capable of listening for weaker signals (Hardly places any load on the antenna terminals) - so the 150Ω or 75Ω or even 300Ω load resistors are not going to sap all that much out of the RF budget for the Receiver to work with.

Thanx so much for the input. I'm going to let him read this and decide what he wants. I try to help everyone as much as I can, but my knowledge is very limited, and I don't feel the need to start telling these guys what they can't do! LOL. I try my best to advise them but, ultimately, it's their money. Thanx again!

 

[Eldorado828]

I must have missed the part originally mentioning it was going to be a kl503, that's a lot of juice especially for that box.

You'd think the radio of choice for that Amp could be a president McKinley.

 

[Greg T]

I must have missed the part originally mentioning it was going to be a kl503, that's a lot of juice especially for that box.

You'd think the radio of choice for that Amp could be a president McKinley.

I didn't know he was going to buy that amp. We were discussing what he wanted at the beginning and just a couple of days ago he sent me a message saying that he found an amp on a good deal and he bought it. I told him he went from a bad idea to a worse idea. That's why I now told him sell the amp, buy the radio he wants, and then we'll get an amp that will match said radio.

 

[magnuman]

Easy to turn down the RF power on the AT-6666 to whatever you want as long as nothing has been touched in the radio. The problem willbe when he turns on the amp and forgets to turn down the power on the radio first!
Good radio. Should have got a bigger amp like a TS DX500...then he will get heard and no need to touch the radio.
I am sure he will need a new amp before too long!
Experience is the best teacher.

 

[Greg T]

Easy to turn down the RF power on the AT-6666 to whatever you want as long as nothing has been touched in the radio. The problem willbe when he turns on the amp and forgets to turn down the power on the radio first!
Good radio. Should have got a bigger amp like a TS DX500...then he will get heard and no need to touch the radio.
I am sure he will need a new amp before too long!
Experience is the best teacher.

Well, I guess plans have changed again. Cuz sent me a text tonight stating he already ordered a Stryker 955hpc. It'll be here on the 25th and he wants me to set it up for him. Ya have to love it when someone asks for advice and assistance, but does the opposite of what is recommended. I guess I'll be asking which pots turn the SSB and AM low power down on the Stryker pretty soon! SMH!!

 

[Eldorado828]

Well, I guess plans have changed again. Cuz sent me a text tonight stating he already ordered a Stryker 955hpc. It'll be here on the 25th and he wants me to set it up for him. Ya have to love it when someone asks for advice and assistance, but does the opposite of what is recommended. I guess I'll be asking which pots turn the SSB and AM low power down on the Stryker pretty soon! SMH!!

Makes you wonder why they even ask.... I've got a coworker and friend that do exactly as that haha, I know the feeling.

Makes you wonder if we should say the opposite of what we really want to say .

With that 955, he's gonna need an even BIGGER amp if he's dead set on using one..... but like the 955's quad 6 cousin, it should do great all by itself with the proper antenna.