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I believe I have the main dial set properly now.
Putting the scope on TP019 I get no waveform unless I move the MHZ dial down to the zero mark (where the led goes out) then I get the waveform below. It does not change when moving the second VFO.?

But when I put the scope on TP401 I do get a waveform that changes in frequency from 3.35 mhz to 2.42 mhz when I tune the second vfo from 0 to 1000. ? ? I hope all this is making some sense and helping!!!




Also checked to make sure that VR102 is not full on. It's at it's aprox. mid point.

I believe the HG is dead. I did as you suggested with a SW SDR and I do not detect any signal at all tuning up and down, and putting the scope on TP106? the output from the HG shows nothing. It is getting the 9V supply
Is there a process to check the crystal?

I really appreciate your help with this..

The HG should provide a very strong fundamental tone at 1 mHz,? especially when the box is removed from the chassis and powered. . Its not uncommon for the crystal to fail. The HG output is at a very low level, a spectrum analyser? is handy here. But, any SW radio placed near will find the harmonics from 1 to 35 megs as you tune up and down the spectrum... use SSB if you have it. thats where those small Chinese radios are handy for this. There is little to check in there really. The two diodes clip the oscillator output giving the distortion to create the harmonics, I guess these could fail, but doubtful.

Your other questions.....
The slight? resistance you feel at the tuning edges is normal, and is to do with the mechanism limiting the end stops.
By loosening the tuning drum center nut,? it can be easily adjusted to agree with the kilocycle markings if the basic arrangement is ok.?

I don't think the HG unit is running. Putting the scope on TP106 I get nothing. It's getting the 9 volts.
I haven't as yet? popped the lid off the HG enclosure.

Yes, you need to fix those? mechanical issues first. It seems someone has really fiddled with this one
The kilocycle tuning capacitor needs careful setting up. With the vanes fully closed, the tuning shaft should be against the stop, and the tuning? indicator? should be aligned with the small triangle mark on the right hand side of the tuning drum.. The tuning cap is not used over its full travel, this is done to give a more linear readout on the scale.? It is normal for the tuning cap to not fully open, so perhaps this has not been changed.? This is a pain to get right, and you will need some very small allen keys to loosen the grubscrews if repairs are needed..
For completeness, the second VFO ,or kilocycle oscillator should be checked, it will run from 2.455 megs to 3.455 to give the 1 meg tuning increments.... and remember it actually tunes backwards.
Connecting your scope to TP109 should reveal a rising and falling waveform amplitude as the Megacycle knob is varied, but the scope will need to be a good one, this section is at 50 odd megs.
If you dont see any waveform here , the fault is either the amplifier chain or the harmonic generator. Sometimes the mixer chip will take a hit, but seldom.
Also check VR102 hasnt been wound fully on. This preset alters the bias on the LED lock lamp, It should go off at one extreme. This section rectifies part of the selective amplifier output signal to indicate correct tuning.

Screen grab of output from osc board. Freq varies smooth from 83 mhz @ 29 mhz down to 54 @ at 0 mhz
taken at TP 101 /102 gnd.

Pentagrid, thanks for the reply.

I did the tests as you described and I could not get any signal on the AM radio tuned to 1mHz positioned near the mixer chip.
But I did get a signal at 84mHz when the mHz knob was set at the 29 mHz position.

Test gear, I do have an oscope, a vintage HeathKit signal generator (restored and works well), a cheap signal tracer, and Multi-meters.

Also another issue I should mention with this radio is that the 1Mhz tuning dial does not move properly. Rotating the large tuning knob to the left the drum display stops at the 200 mark.
When rotating to the right it goes past the 1000 mark to just beyond the small triangle. In observing the related tuning capacitor I do notice the capacitor plates do not fully open nor fully mesh at the ends of travel.
Also i feel a slight resistance in the knob when approaching both ends of travel. I read in another post that lubrication may be the problem but that did not seems to help unless the lube was not applied in the right place.
Do you feel this issue should be addressed prior to the lock light issue??

Brian

The above should have the FM radio tuned to 84 mHz, my mistake.? Most modern digital RXs will tune this low.
To test the selective amplifier you will need? some test gear, do you have any?

The only section you need look at is the 52.5 Mhz selective amplifier as mentioned in that article. Unfortunately, that article refers to a receiver that is already functional, yours is not. Therefore, any alignement suggestions cannot work in your case.
You need to fault find.
The selective amplifier mixes the VHF oscillator, this is the Megahz knob, and the output of the harmonic generator.
Check both these sections .?
If you have little to no test gear, do the following.
To test for harmonic activity in the HG, place a normal AM radio near the first mixer chip, located on the front right of the left? hand PCB. A blank carrier should be heard on the AM radio at 1 mHz.
With an FM radio tuned to 88 MhZ,, the FRG7 megacycle oscillator should be heard on the FM radio when tuned to 29 mHz.
If you hear these, then the fault lies either in the mixer or following amplifier

Greetings, I was given a FRG-7 by a friend. No clue as to the history of this radio. After cleaning all the rotary switches and volume pot I was only able to receive some local AM broadcast as the zero blob on the MHZ dial is the only spot on the MHZ dial where the lock light would go out. Tuning up through the entire MHZ range the lock stays on.
?In reading many posts here it was mentioned to slightly tweak VR102 to get the lock to work properly but no joy.
So I'm at the point of deciding to try a quick alignment as described in the link below or hopefully someone here can suggest other items to check.


Thanks in advance
Brian / N6RZR

Yes. Look at /g/Yaesu-FRG-7/files/2%20-%20Forum%20Rules%20Folder/Yaesu%20FRG-7%20Rules,%20For%20Sale%20or%20Want%20to%20buy%20Posts.txt for selling rules.
73 Roger VE7LB group owner

Are FRG-7 for sale ads permitted ?

Hello,

For someone who is interested. I've posted a short video on Youtube with the right alignement procedure for the LSB and USB offset.


Have fun and enjoy the FROG 7.

Marcel

And if you would like to see the digital readout in action, here is a Youtube link:

73, Marcel de PA8MA

Just a short update about the Ebay link.
The previous link has disappeared because I ran out of stock.
This is the new one for someone who is interested



Regards, Marcel

A quick pic of the few mods I have done to this radio, two diode switched filters, these are? selected via the existing mode switch, SSB/CW? and AM /ANL positions select the narrow, and wide respectively.
As I have previously mentioned, the existing BFO is NOT adequate to service a narrow filter, its long term instability will eventually move it out of the passband, ceramic resonators will do the job, and can be "pulled" to sit on the filter skirts properly.
Other mods done include AGC fast/slow, AGC also applied to the first IF amplifier, and others that escape me at the moment.
But, everyone loves pictures........

Here is the plastic lid I used, almost any lid will do, but make sure the wife is away when choosing. I thort bright pink was rather fetching.

The FRG7 has around 12 turns of the tuning knob to cover a 1 meg band segment, pretty fast, requiring the finesse of? safe crackers hands to tune in that ssb station, especially when the machine hs been fitted with narrow filters.
Here is a very simple mod to slow? that tuning speed to 75 turns band end to end.
Remove the central plastic tuning dial from the kilocycle tuning capacitor, held on by one central nut, careful maneuvering? under the S meter will see it free.
Remove the three wires from this capacitor, remove the main tuning knob and carefully lift it out.?
?Buy? a ball reduction drive, these can be got almost anywhere, and eye up the space available after removing the front facia plate.
Two 2.5 mm holes are drilled into the front chassis to mount the added ball drive in line with the existing tuning shaft.
The existing tuning shaft will need shortening, use a hacksaw.? Measure carefully.
The radio can now be reassembled. The kilocycle tuning capacitor can now be slid back into the existing cavity another 15mm or so, and new mounting holes drilled to reattach it to the chassis.
Reconnect the three wires to the tuning capacitor.
The dial drum is now too small. I found a plastic jar lid? the right diameter and drilled through the center to mount it to the shaft.
Masking tape around the edge can be used to mark the 100 and 10 kc increments accurately as the radio is tuned, then this is transferred to a drawing program to make? A professional looking dial..... Im still getting round doing that part.....
Tuning is now so much easier, and the fine tune is no longer needed..

Originally, the kilocycle tuning is mounted forward toward the front panel as here.

.
....

After the mod, it is mounted toward the rear, you can see the added ball drive on the front panel...

Here is a simple realignment method requiring few test equipments.

https://worldradiohistory.com/UK/Short-Wave-UK/80s/SWM-1981-10.pdf?

Thanks again everyone for the responses.?

I do not own an oscilloscope, been meaning to get one for some time now. I think that is the only way I can get further diagnosing, as I am not used to transistor gear or wadley loop receivers, I have only repaired tube gear and built Regen receivers before, never toyed with something like this. I only own several DMMs, a VTVM and a basic Heathkit analogue RF generator.?

An update on where I am at right now - I removed all the solder off the board besides the blob on L101. The remaining blob was on c117 next to T05 and T06 and was not electrically connected. I am glad that coil L101 is not critical for SW listening. I was not looking forward to winding a coil that small.

The receiver has not worked at all since my initial post. I will better describe the behavior here:

The lock light only goes out when the MHZ dial is tuned to 0, peaking in noise to the right of the 0. The light however will not go out when the band switch is set to the AM band, only on bands 2-4. The preselect still does not seem to have any affect on this. I do get S meter movement when tuned here.?

I will see if anyone local has an oscilloscope I can borrow, or maybe look at getting a used one.?

I will try reflowing the board as suggested, in particular I will focus around the IF cans. I will only use a soldering iron because as Pentagrid pointed out old PCBs are fragile and not up to the task. I plan on working on different parts of the board simultaneously to spread the heat out better.

Any other suggestions before I look for an oscilloscope?