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I am beginning to think this radio is actually fine, it has been misaligned.? The VFO, "mHz tuning" should span from 55.5 to 84.5 mHz.? The first IF should be centered on 55 mHz, this can be checked by feeding in a small signal into the IF chain and monitoring the output at the second mixer. The Wadley loop section should be centered at 52.5 mHz, this is checked at the source of the second mixer.? The difference frequency between 55 mHz and 52.5 mHz is 2.5 mHz, the center frequency of the second tuneable IF.? When peaking/adjusting these IFs, use a very low amplitude signal as not to overload any part of the circuitry. Its just a process of elimination and perseverance........

Just wanted to publicly thank a member here for privately offering FRG7 parts.
Good people here.

I've put the FRG7 aside while I torture a Heathkit now.?
If I find a fix in the future, I'll update.

73 for now.
--
-Bob

Latest update:
Q105 just doesn't seem to want to mix.? It tests well, but it is producing 42MHz instead of the 2-3MHz. ?? The 2 IFs coming in to it are fine.
So I am going to order MPF103's (can't find any 2sk19gr's).?
Meanwhile I'll check all surrounding components to make sure they don't have an issue.

The saga continues....
--
-Bob

Come on guys.? Enough
.
I bought the FET from a Canadian EBAY seller & when I told him, he immediately refunded all money including shipping.? It was during Easter & he was on vacation but still responded.? He has a 100% rating there.

I know there is too much bogus stuff out there, but this isn't one.
I buy a few things on EBAY & have only gotten burned once.? Maybe I am lucky.
--
-Bob

Accusing Mr Elliot of lying? Certainly not, and what a stupid allegation.
I do however question the parroting of unsolicited allegations of fake components from unknown sources. For instance, unwanted parasitic oscillations are common in high gain audio designs, and can destroy ANY? output transistor even at quiescent .
Many of these reported failures are from non technical people who either lack the knowlege or equipment to track this phenomena, let alone cure it, they are merely following a diagram, or a plan, with the expectation it will work.
One contributor sites a? 2N3055 transistor failing at 4 amps, so it must be a fake. The genuine transistor is rated at 15 amps Ic, max CE voltage 60 by memory. Without any more technical context by the contributor, we cannot diagnose anything. What was the supply? voltage? What was the base current? Was the transistor in saturation? What were the thermal conditions.????Not enough evidence here to allege fakery.
?Was? this gentlemans expectations rather? too high, his understanding too low? perhaps?
To accept this as evidence of a fraud is ridiculous.
?I am sure fake components do exist, but not on the scale you would like to believe.... my initial point.
Even your friend Mr Elliot agrees with me that distributors making a living knowingly selling fake transistors are unlikely to remain in business long, so in that regard, its a self levelling process.?

So, please do not offend me with your assumptions.

Clearly we disagree

This is getting off topic, my final comment.
If fake transistors predominate just the audio world, it does beg the question, why??
Vacuum tubes for instance , they look for the brand name, the colour of the getter, the gold plated pins.
We look for heater? to Cathode voltage, Gm, Mu, plate dissipation and grid bias. Transistors we look at HFe, SOA, Ft, Vsat, among others, not the colour, the hype or the "sound" or whether its recommended by some audio expert down the road, we care not about such things.
Do you seriously expect me to give a "list" of my suppliers, this would take hundreds of pages.
As I have said, only VERY occasionally you "may" have a problem, in which case, if suspicious, or suspect, simply MEASURE the component parameters first ,thats what? competant techs do. There is no excuse for fitting suspect parts , or substitute parts without..... potentially damaging the equipment under repair.

By the way, did you just call Mr. Elliott a liar? He is A PROFESSIONAL

I am just passing along what almost EVERYONE on audiokarma and DIYAUDIO websites says…..
they are full of ordinary people getting fake semiconductors!
many of the people giving these warnings are pro, who have been in the audio hobby for many years…..

could you provide a list of eBay sellers who can be trusted to sell genuine semiconductors, there are many many people including myself would would LOVE to know who we could buy from on eBay

You stated unequivocally that "most transistors sold on Ebay are fake".? This is untrue and an unfair generalisation.
More correctly, SOME transistors sold on Ebay are fake. .
There is a simple reason for this.? Any supplier repeatedly selling known fake semiconductors would soon not be in business.
It is also very common for a failed repair by an untrained hobbiest to be blamed on faulty components. I repair this type of equipment regularly, its been a very good little earner.
I operate an electronic design and repair shop, concentrating mainly on the repair of legacy equipment. I have been reliant mostly on the same Ebay suppliers you mention,? to supply discontinued/obsolete semiconductors, and have twice in 30 years had occasion to question a supplied component/product. This suggests that the "fake" semiconductor problem is not as widespread as is liked to be believed., and I buy a large amount of random semis from random overseas suppliers.? Others in the industry also tell me similar, I have no reason to doubt them.? They also derive a large part of their repair revenue from well meant but? failed repairs? based on youtube videos or mods? performed by the hapless owner.....

this is one of the many many threads on fake semi conductors from China and eBay



this article is most useful

thats not what the people on all the audio sites say, do the research please

I would not be so scathing, most transistors sold on Ebay/Aliexpress? are not fakes. Also bear in mind these dual gate FETs are static sensitive and may have been stored/handles incorrectly by previous warehouses/distributors, or even inadvertantly damaged by the purchaser without any knowlege. Dual gate FETs , even NOS are getting on in years, they are becoming a rare component these days.? Many sellers too, have no idea of what they are selling. The early 2/3 SK series dual gate FET lacked any internal gate protection diodes and were prone to gate "punch? through" by static voltages, the later types, the 40673 for example did have the protection diodes, and therefore more robust with handling.

Most transistor sold on eBay are fakes. You should file a claim and get your money back.

Update:
New 3SK40 I bought off of Ebay is bad.? Same problem as the old one: G2 is kaput.? So I ordered a NTE222 from Amazon.? Awaiting delivery.
I also found the ATTN switch has seen an EMP.?? Many of the resistors are fried & one was blown in two.
So now I wait....
--
-Bob

As the saying goes, I am self taught & I had a bad teacher.
I got the scope out (means I am desperate) I can see the 1st & 2nd ocs.
I can see the lock unlock working & the comb freq on the scope.
I pulled Q105 2nd Mixer & Q104 and both tested fine.
But I see very little at TP107 coming out of the premixer IC Q106.
And I do not see the 3MHz coming out of the good Q105 over to the IF/AF board.
So I am thinking it maybe that IC Q106 or maybe someone messed with the alignment.

Thanx for the comments.? The slog continues...
--
-Bob

And, if the previous guy has twiddled the 1st IF? coil tuning slugs, it will need a realignment in that section. Correct alignment here is crucial.

Well, it seems the tuneable IF section, 2 to 3 megs is working, the loop section, ie, megacycle selector is working, so the money goes on the second mixer back. This is a juncton FET, it may be open. There is little to go wrong with the 55 meg first IF section, there is a dual gate FET in there, that never gives problems, neither does the front end balanced mixer. So, i would check the second mixer, just replacing it is easy and cheap? and will eliminate that one.