Purchased a mint RS-218 SDR to dip my toe into digital.

Arrived perfectly packaged and as mentioned mentioned "mint" ... no adverse comment on seller who said working 100% the day before despatch.

Unfortunately on start up VFO was "doing its own thing"... ie turn forward and 14.000 and click a few notches on and went 14.000 then down to 13.998 click again and up to 14.123. If you slowly fowarded the VFO it would go one digit at a time and suddenly go the alternative ... 14.500 - backward to 14.499-14.998!

I had changed the waterfall/spectrum to specscope via menu playing around but that is the only move made.

Radio does not want to play as each click of the VFO may go up 1kz or + or -! Something wrong?

Any advice would be helpful.

I accept I did go into the menu to change from waterfall/spectrum to spectrum but do not think this procedure would cause VFO tuning to be erratic ... up or down!

All help would be kindly welcomed or would you go to a site that would give a complete installation and where would this "go back to starter" be alternatively you have bought a duffer?

I am quite prepared to take the "hit" on the radio and have a lovely lump of brick to keep the door open but cannot for the life of me think by changing the waterfall/spectrum to spectrum would cause this radio to freak and turning the VFO to go up maybe 1kz or down 3kz then up 10kz!

Looking forward to any help. As mentioned I have paid for it and hey ho it isn't working but that is the choice you make purchasing not face to face.

Keep safe
MW1RES

Re-install the latest widely used firmware.

If that doesn't help, replace the rotary encoder.

They can be quite fiddle to take apart, so while you have it apart, check for any mods and put some decent heat sink compound on the regulators and finals.

The process to install the firmware is well documented and straight forward. I think you need an adaptor for the USB connection. (I have some in a draw and I think that is what they were for)

Otherwise, if you don't want to work on it, sell it faulty and cut your losses, the cost of labour will probably make it uneconomical to have it repaired.

They work very well if you get a good one, but the quality control was non existent, lots of issues came up. (No different to MFJ though)

Also, if you do a full reset, make sure you get the correct settings for the final's bias, if you set it as the "original" instructions, you will cook the finals.

It's 3-4 years since I worked on one, so the above is just a pointer, the details will need checking, they are all easily available on the net though

Cheers for the information.

I am checking all angles on Google and of course on here. It is one of those scratch your head times. The VFO control knob started the problems when turning up or down the readout was 1kz then next turn 3kz and next turn -2kz!

As you say it maybe easier to take the hit on the radio and sell as spares but will give it a go (must try something) and if no go I have a lovely 3lb lump hammer that can be introduced into the equation (frustration may have set in by then)!

Got plenty of time to play so will keep hunting.

There is a setting that controls the acceleration of the main tuning I think, if you turn it very slowly, does it work evenly then?
I think you can also set it at a fixed instead of variable rate. (may be getting confused with the uBITX)

The encoder could also easily do that.

If you do a full reset, it might help, but it you do, it won't transmit until you have set the bias, so have a look what that is before you reset. It will be a lot lower than a manual may suggest.

Thanks for more info.

Certainly got a lot to work on ... will call it a "project"!