01-04-2016, 07:34 PM
Yesterday, I decided to bring down from upstairs this Eddystone 670A radio receiver.
Upon trying it out I was somewhat disappointed in it's performance, it was absolutely hopeless on short waves and nothing special on medium and long either.
In fact my 1936 Pilot X65B is vastly superior performance wise.
Both these sets have an RF amplifier stage and proper coil packs. The Eddystone has more modern valves compared with old timer UX base tubes fitted in the Pilot, the Eddystone should be much better.
Today, I decided to tough it out and find out what is wrong with the Eddystone.
Starting with the usual tests such as valve voltages and component checks everything seems in order.
Time to check the of the IFs and the trimmers and inductors in the coil pack.
Switch to long waves and force feed the receiver with 450Kc/s. sure enough the IFs are way out. Peaking them up on 450Kc/s results in a vast improvement. Off tune a healthy hiss can be heard, things are getting better already. Attention was turned to the coil pack to retune the aerial, RF and oscillator coils.
After carrying the adjustments according to the instructions in the Eddystone service manual the receiver is very lively on medium and the two short wavebands. Still not very good on long waves, but that's how it is here in the North-East of England.
This evening I'll connect the set up to the tuned frame aerial in order to compare it with the Pilot X65B.
I'll report my findings in due course.
The appearance of the 670A: http://www.shortwaveradio.ch/radio-e/edd...670a-e.htm
Geordie McBoyne.
Upon trying it out I was somewhat disappointed in it's performance, it was absolutely hopeless on short waves and nothing special on medium and long either.
In fact my 1936 Pilot X65B is vastly superior performance wise.
Both these sets have an RF amplifier stage and proper coil packs. The Eddystone has more modern valves compared with old timer UX base tubes fitted in the Pilot, the Eddystone should be much better.
Today, I decided to tough it out and find out what is wrong with the Eddystone.
Starting with the usual tests such as valve voltages and component checks everything seems in order.
Time to check the of the IFs and the trimmers and inductors in the coil pack.
Switch to long waves and force feed the receiver with 450Kc/s. sure enough the IFs are way out. Peaking them up on 450Kc/s results in a vast improvement. Off tune a healthy hiss can be heard, things are getting better already. Attention was turned to the coil pack to retune the aerial, RF and oscillator coils.
After carrying the adjustments according to the instructions in the Eddystone service manual the receiver is very lively on medium and the two short wavebands. Still not very good on long waves, but that's how it is here in the North-East of England.
This evening I'll connect the set up to the tuned frame aerial in order to compare it with the Pilot X65B.
I'll report my findings in due course.
The appearance of the 670A: http://www.shortwaveradio.ch/radio-e/edd...670a-e.htm
Geordie McBoyne.