VK Amps KM3KM Sampler Comparison

[KD1GA]

both samplers.jpeg (3.26 MiB) Viewed 2332 times

VK Sampler.jpeg (2.94 MiB) Viewed 2332 times

KM3KM.jpeg (3.05 MiB) Viewed 2332 times

[w-u-2-o]

-65 dB is too much. The -55 dB of the VK unit is perfect at the legal limit.

[RobB]

signal levels aside one unit looks to be professionally made the other a junkbox special.

[Dan]

I purchased the VK model specifically because of the surface mount resistors. This keeps the traces short to them. And as Scott says, -55 dB is perfect, at 5 watts or 1500 watts. I never have to add additional attenuation.

73, Dan

[Dennis]

That is not a Comparison,

have been using and sending and recommending VK-AMPS sampler for years, stable and in some instances, works better then the Internal OM amp fitted unit, plus other amp manufacturer's factory fitted sniffers,

I have tested VK-AMPS samplers with
SPE, 1.3,1.5, S2/S3, SPE 2KFA
VK-AMPS air cooled and water cooled,
THP
FL-7000
9500
A87A
8410
AL-1500
AL-1200
AL-82
AL 800H
ACOM 1500
Acom 2100
Acom 2000
using
ANAN 200D, ANAN 7000 DLE MK II, ANAN G2 radios ( with Excellent reports from HERMES LITE users in EU using the VK-AMP sampler,

well made stable, value for money,
his amps a Beasts, the Water Cooled 2 X 1K80 65V is a BEAST on Steriods after sniffing angle dust,

Cheers
Dennis vk4sx

[w9ac]

Thankfully, RF is visually blind. Some of best performing devices I've measured are aesthetic nightmares (and vice versa).

I've no idea about the KM3KM sampler but it's likely a local project from Miami. My understanding is the Lux and Mercury III amps are designed by RZ1ZR (not just the LCD display) and assembled by KM3KM in Miami, despite all the PC board nomenclature that suggests otherwise.

Paul, W9AC

[rdwing]

Thankfully, RF is visually blind. Some of best performing devices I've measured are aesthetic nightmares (and vice versa).

I've no idea about the KM3KM sampler but it's likely a local project from Miami. My understanding is the Lux and Mercury III amps are designed by RZ1ZR (not just the LCD display) and assembled by KM3KM in Miami, despite all the PC board nomenclature that suggests otherwise.

Paul, W9AC

I don't think so. The same sampler could be found on ebay for $30 from China, although now I only see the same units claiming made in USA.
I would not want to send legal limit through that.

The VK3AMP sampler is beautifully constructed, with actual test and validation data available. Everything Onder makes is impressive. That's the sampler I recommend to folks.

I would also not recommend the cleanRF sampler, if only because the signal is run through a variable pot and does who knows what to it, with the added risk of blowing up your ADC.

[RobB]

Thankfully, RF is visually blind. Some of best performing devices I've measured are aesthetic nightmares (and vice versa).

I've no idea about the KM3KM sampler but it's likely a local project from Miami. My understanding is the Lux and Mercury III amps are designed by RZ1ZR (not just the LCD display) and assembled by KM3KM in Miami, despite all the PC board nomenclature that suggests otherwise.

Paul, W9AC

If you take a look at RZ1ZR website. specifically his amp control boards I think you may change your mind. He has a great aesthetic look in the display and his firmware does a fine job but his own hardware comprises a bunch of cheap modules soldered to a carrier board, lacking any kind of integration. He supplies the firmware to various boutique amp makers KM3KM, Vk-Amps, EB104 and soon Apache labs. In each case the makers have developed their own control boards around his firmware. To compare his hardware implementation to the "hardware guy's" efforts the difference is chalk and cheese.

[w9ac]

Dig deeper.

I found the LPF board designed and manufactured by RZ1ZR, saved by archive.org in 2018. It no longer appears in the same form and layout as shown on his current website.

Now compare it to the Mercury III LPF board as shown by AE5X on his blogspot.

Both images attached.

The topic is about the RF sampler. I'm simply questioning its origin as well as the amplifier circuit boards. I've no issue claiming something is "designed and manufactured in the U.S.," provided it actually is.

Paul, W9AC