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 Post subject: FRG-7000 Alignment?
PostPosted: Sep Fri 17, 2021 11:56 pm 
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Joined: Apr Fri 23, 2021 8:19 pm
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Location: Richardson, Texas, 75082
I have a FRG-7000 which appears to be working but since I just recently bought it off ebay I thought I should check the alignment.

In the manual there is only 1 page for maintenance and alignment.

I'm having difficulty understanding section 6 and 7, second and third IF alignment, it does not make sense to me..

for example it says set sig gen to 2.9 mhz and display should read 100 khz?, don't understand this

the instructions seem to be very not detailed

Can anybody familiar with this receiver throw some light on this

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 Post subject: Re: FRG-7000 Alignment?
PostPosted: Sep Sat 18, 2021 10:00 pm 
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Joined: Mar Mon 17, 2008 5:05 am
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Location: Ashhurst, New Zealand
You can't 'second guess' some of those Wadley Loop radios - just do it like it says. Those instructions look pretty specific, they say that the radio display should say '100kHz' just for info, they want you to adjust a couple of trimmers for max 'S' meter reading. You can see that the second IF oscillator is working in the reverse direction, 2.9MHz is the low frequency end, 2.1MHz is the high frequency end of the scale. You are not injecting the signal into the antenna, you are aligning the second IF.

If you want to try some mental gymnastics, try tuning up a Barlow-Wadley XCR30! You don't have to understand it, just do it!

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 Post subject: Re: FRG-7000 Alignment?
PostPosted: Sep Tue 21, 2021 3:39 pm 
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Joined: Jul Wed 22, 2009 3:07 pm
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If you look at the block diagram on pg. 13, that IF-AF unit is a tuned receiver, within the receiver, it tunes from 2MHz to 3MHz.
TO1 and TO2 (as marked on the schematics) are the RF part of that receiver, those are tuned by VC2.
So you tune it up at the bottom of the band with the coils, at the top of the band with the trimmer caps.

Regards, Peter


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 Post subject: Re: FRG-7000 Alignment?
PostPosted: Oct Tue 05, 2021 5:36 pm 
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Joined: Apr Fri 23, 2021 8:19 pm
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Location: Richardson, Texas, 75082
majoco wrote:
You can't 'second guess' some of those Wadley Loop radios - just do it like it says. Those instructions look pretty specific, they say that the radio display should say '100kHz' just for info, they want you to adjust a couple of trimmers for max 'S' meter reading. You can see that the second IF oscillator is working in the reverse direction, 2.9MHz is the low frequency end, 2.1MHz is the high frequency end of the scale. You are not injecting the signal into the antenna, you are aligning the second IF.

If you want to try some mental gymnastics, try tuning up a Barlow-Wadley XCR30! You don't have to understand it, just do it!


I finally figured it out, I had misread the instructions slightly, I was able to peak the IF slightly, did not need much adjustment.

Radio is pretty sensitive

I appreciate your reply

thanks


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 Post subject: Re: FRG-7000 Alignment?
PostPosted: Oct Tue 05, 2021 5:37 pm 
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Joined: Apr Fri 23, 2021 8:19 pm
Posts: 118
Location: Richardson, Texas, 75082
orbanp wrote:
If you look at the block diagram on pg. 13, that IF-AF unit is a tuned receiver, within the receiver, it tunes from 2MHz to 3MHz.
TO1 and TO2 (as marked on the schematics) are the RF part of that receiver, those are tuned by VC2.
So you tune it up at the bottom of the band with the coils, at the top of the band with the trimmer caps.

Regards, Peter



I finally figured it out, I had misread the instructions slightly, I was able to peak the IF slightly, did not need much adjustment.

Radio is pretty sensitive

I appreciate your reply

thanks


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