ZX60-P103LN+ LNA Schematic and Parts List

[EricCottrell]

Hello,

I followed the suggestions on RR and got a ZX60-P103LN+ Low-Noise Amplifier. It recently stopped working and I opened it up to see if I could find some information on it.
https://www.minicircuits.com/pdfs/ZX60-P103LN+.pdf

The amplifier is a PGA-103+.
https://www.minicircuits.com/pdfs/PGA-103+.pdf

The datasheet mentions an Eval Board TB-761-103+ which has the same layout as the preamp. The 349-28 numbers are on both PCBs! There is also a parts list.
https://www.minicircuits.com/pcb/WTB-761-103+_P02.pdf

I thought maybe the ESD diode shorted, but it was okay. The PGA-103+ is getting power, but no amplification. I am going to see if I can get a new PGA-103+ and have the rework person at work change it.

73 Eric

 

[prcguy]

A few weeks ago I purchased a pair of the ZX60-P103LN+ amps for a tower mounted filtered preamp project then found some better suited amps with 6dB higher IP1 and flatter response at the Dayton hamster fest at three for $5. If you need to actually purchase a replacement I might let a ZX60 go a little less than retail.

Hello,

I followed the suggestions on RR and got a ZX60-P103LN+ Low-Noise Amplifier. It recently stopped working and I opened it up to see if I could find some information on it.
https://www.minicircuits.com/pdfs/ZX60-P103LN+.pdf

The amplifier is a PGA-103+.
https://www.minicircuits.com/pdfs/PGA-103+.pdf

The datasheet mentions an Eval Board TB-761-103+ which has the same layout as the preamp. The 349-28 numbers are on both PCBs! There is also a parts list.
https://www.minicircuits.com/pcb/WTB-761-103+_P02.pdf

I thought maybe the ESD diode shorted, but it was okay. The PGA-103+ is getting power, but no amplification. I am going to see if I can get a new PGA-103+ and have the rework person at work change it.

73 Eric

 

[ILSAPP]

So what's the veredict? ZX60-P103LN+ is the most suited LNA for use in airband together with a FM notch filter/BPF ?
Any other better alternative?
I'm looking to improve my long range airband reception. I already have an airband tuned antenna.

Thank you

 

[Ubbe]

One PGA-103+ semiconductor are usually $5 incl shipping.
PGA103+ based LNA's are excellent antenna amplifiers for all situations, if you don't have extreme needs and special requirements.

/Ubbe

 

[prcguy]

With a very steep skirt VHF airband only filter it might be ok. Its going to have at least 23dB gain in the VHF air band and that's way too much feeding a sensitive scanner unless you have a mile of coax. You will end up attenuating most of its gain, otherwise your noise floor will be hard to deal with.

The ZX60-P103LN+might be an ok choice if it were the front end of an actual receiver with 4-5dB of band pass filter loss to then drive a mixer.

So what's the veredict? ZX60-P103LN+ is the most suited LNA for use in airband together with a FM notch filter/BPF ?
Any other better alternative?
I'm looking to improve my long range airband reception. I already have an airband tuned antenna.

Thank you

 

[prcguy]

And another thing, the IP1 and IP3 specs on the ZX60-P103LN+ are modest at best, so that combined with the high gain will run this amplifier into problems at a lower level than a similar amp with 12-13dB of gain. You can't fix that problem by adding attenuation after the amp.

I'm finding the need for IP1 specs in the 27-30dBm range and IP3 in the 45dBm or greater range at minimum in a wide band preamp. Noise figure is a little less important than IP1/IP3 in a wide band preamp because it won't matter if you have a low noise figure if the amp is spewing out a high level of crap because its being over driven and creating IMD.

Something else I don't like about the ZX60-P103LN+ is the 10dB of gain slope from 50MHz to 1GHz on this amp. Any other amp I've had that covers this or a wider range held the gain within a dB or so over the entire range.

With a very steep skirt VHF airband only filter it might be ok. Its going to have at least 23dB gain in the VHF air band and that's way too much feeding a sensitive scanner unless you have a mile of coax. You will end up attenuating most of its gain, otherwise your noise floor will be hard to deal with.

The ZX60-P103LN+might be an ok choice if it were the front end of an actual receiver with 4-5dB of band pass filter loss to then drive a mixer.

 

[ILSAPP]

In my case I'm using the Airspy HF+ (dual port: HF and VHF) which has better specs than most scanners. So probably it can cope with strong signals coming from the LNA with its smart AGC.
Agree with the IP1/IP3 topic. Most of us look closely to NF and gain and forget about how important is to have good linearity.
I'll try to find a better suited LNA and just do not go immediately with the ZX60-P103LN+.

With a very steep skirt VHF airband only filter it might be ok. Its going to have at least 23dB gain in the VHF air band and that's way too much feeding a sensitive scanner unless you have a mile of coax. You will end up attenuating most of its gain, otherwise your noise floor will be hard to deal with.

The ZX60-P103LN+might be an ok choice if it were the front end of an actual receiver with 4-5dB of band pass filter loss to then drive a mixer.

 

[Ubbe]

You can't be without a variable 0-20dB attenuator when dealing with amplifiers. There are too many people adding an amplifier and then says it doesn't work and only make things worse. There's hardly any scanner type of receiver that can handle even a 10dB gain increase at its antenna port from an amplifier. A cheap $20 attenuator that has a continous setting from 0-20dB are very useful in all radio receive situations to let a receiver get just enough signal increase to not cause sensitivity degrading.

Commercial radios have front-end filters that are 2-3MHz wide and can handle high signal levels but scanners have something like 50-100Mhz, 130-200Mhz and 500-900Mhz filters that let too much signals pass that you currently are not monitoring and overdrives the scanners receiver, first degrading it's sensitivity and with stronger signals goes into intermod.

/Ubbe