Lowe SRX-30 muted from 0.5 to 7MHz

[Libratron]

Hi at all.

I have buy this partially functional HF receiver
to fix it and maybe listen. The receiver is a Wadley loop type.
Basically, it's mute from 550 kHz to 7 MHz; from 7 MHz to 30 MHz have a good reception. I have opened and i see it the two integrated TTL dividers are still the originals, but socket. For the rest it's all original. I ordered a couple of new dividier ICs, hoping to replace them, to have the whole band from 0.5 to 30 MHz. I read that it is a typical fault of this receiver the faulty dividier TTL IC.

Is there anyone who has experience with this type of receiver?
It is also a clone of the Century 21, made by Seiki Electronics.

Thanks,

Libratron

[John KC0G]

There is a 4-position band switch on this radio. On the Lowe SRX-30D, the ranges are 0.5 - 1.5, 1.5 - 5, 5 - 12, and 12 - 30 MHz? Are they the same on the SRX-30?

I have two thoughts:
1. Is the HF oscillator tuning over its correct range, ie approximately 45.5 to 75.5 MHz?
2. Could something be wrong with the band selector switch? It switches three connections to four different coils. It might benefit from a good and careful cleaning. The radio is over 40 years old. But if the possible band ranges listed above are correct, they do not match your symptoms.

I am the owner of the LoweHFReceivers group at groups.io See: https://groups.io/g/LoweHFReceivers You are welcome to join. There you will find a circuit diagram. The quality is not good but it is usable.

Good luck and 73

John

[Libratron]

Hi John,

yes have same selector of the SRX-30D.
Sadly i don't have any frequency counter arrived to read this frequency,
i don't have any type of RF instruments to check it.

The band selector seems to working good.

73

Libratron

[Libratron]

Sadly after change the IC the receiver stay muted on the 0.5 to 7 MHz.
Probably need alignment, i'm not able to do this.

73 at all.

Libratron