Need suggestions on choosing NanoVNA-H and my LNA setup for H1 line observation

[NISHANTH D]

First of all, thanks Alex for helping with my loop feed. I was looking for some suggestions regarding my setup. We're building a radio telescope for the H1 line observation using mostly discrete components.For the LNA stage, we have decided to go with SPF5189Z , since it operates from 50MHz to 4000MHz. We expect around 14dB gain near 1.42 GHz from its datasheet, which is still lower than what sawbird can provide,so we decided to use two stage LNA design and for filter we choose the design from Matjaz Vidmar's Practical Cavity filters for the frequency range 1GHz..4GHz.We've now have successfully constructed both our loop feed and the  cavity filter , but the main issue is tuning our filter and verify that our filter and feed are working properly, but getting access to VNA at nearby college's and institutions for s parameter measurement are expensive and the prices are almost high as buying a new nano VNA-H with frequency range 50kHz-1.5GHz.I'm bit skeptical about relying on NanoVNA-H because the working frequency is near the upper operating limit, I'd really welcome suggestions or experience reg.. choosing VNA or if any low cost alternatives and comments about my setup.

[Alex P]

FYI, this looks as if it may be a Cold Solder Joint .. the solder should flow into the threads

'wiggle it' a bit .. if it comes loose, ReDo with a small torch.

If it is, you will get poor performance not know why !

. 

[b alex pettit jr]

[Jason Burnfield]

I've had excellent results testing several Nooelec Sawbird +H1 LNA/BPF assemblies and various cantennas and a very similar loop feed using the Nano VNA. Even though it only goes up to 1.5 GHz, it has enough coverage to clearly measure performance near and around the hydrogen line frequency.

[b alex pettit jr]

I have one of these ..

 I use LMR400 on some setups ( TypeN connectors ) and the TypeN connector is not as fragile as the SMA  ..

 3Ghz range

It has survived 5+ years of quite frequent use :)

[NISHANTH D]

I will definitely look for any possible defects in my feed solder.Also If anyone here worked with similar filter and lna setup, it would be really helpful, if you could share your experience.

[b alex pettit jr]

I made this solder connection with a fully heated 80W iron .

tin the connector with a large solder blob.. ensure it wicks into the surface, 

     tin the end of copper wire .. 

        join.

[Stephen Arbogast]

Here  is what I  have used  for several years  and works  well. There is  a version newer than mine.       https://deepelec.com/nanovna-f/

Nano VNA Saver   is helpful  software.    https://nanovna.com/?page_id=90

Also you  will need some attenuation.   https://www.amazon.com/dp/B07YYMT65T

Stephen