Suggestions for 1Hz to 500kHz Signal Generator

[HUGH]

I bought a cheap DDS signal generator for testing audio, LF and MF amplifiers and it had such poor waveforms I applied to Epay for a refund. This is likely to be forthcoming but there seems to be a dearth of anything at an affordable price. Any suggestions would be welcome, I don't mind making up a kit.

[PA5COR]

Maybe this?
https://www.amazon.com/TOTMC%C2%AE-1HZ-500KHz-Function-Generator-Triangle/dp/B00NU8ECRQ

Or build the ARRL one
http://www.arrl.org/files/file/QEX_Next_Issue/May-Jun_2013/Fernandes_QEX_5_13.pdf

[KG4CGC]

KKmoon has some awesome stuff!

[HUGH]

Thanks 'Cor. I'll have a go at the one on the ARRL site. The other one, the FG-100, looks OK and it's neat and compact but all waveforms above 10kHz were poor and, except around 1kHz, the audio waveforms had serious, synchronous blips appearing. At 100kHz all waveforms looked like mountain ranges. I sent output sample pictures to the supplier but they were completely clueless.
I reckon my sample was faulty because the construction quality looked good and these must be selling. Frequencies were all pretty accurate.