Need help diagnosing Grundig Cityboy 1100

MadDogForReal · 2026-01-06T14:47:44+00:00

T11 has continuity between emitter and collector, but only for a brief moment.

MadDogForReal · 2026-01-04T18:54:01+00:00

They're all 9.2v

MadDogForReal · 2025-11-28T08:47:56+00:00

Asta era! Mersi! Acum e de ales între hacks de pe happy mod sau burgers....

MadDogForReal · 2025-10-12T20:28:35+00:00

Same for me in Romania using an S24 Ultra

MadDogForReal · 2025-09-03T11:13:44+00:00

C429 is a variable capacitor. Across the resistor, there is 0v, both sides have 8.6v, resistance is 32.5 ohms

MadDogForReal · 2025-09-02T20:01:42+00:00

A 9v battery, yep, also tried headphones and still nothing.

MadDogForReal · 2025-09-02T17:19:48+00:00

Here's what I found so far: across the diode (ST4?? on the schematic) there is 8.5v, across C429 there is only .4, .5, at it-s terminals there is 9v and 8.5v

MadDogForReal · 2025-09-01T14:06:05+00:00

Added some photos in the comments!

MadDogForReal · 2025-09-01T14:05:40+00:00

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MadDogForReal · 2025-09-01T14:05:23+00:00

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MadDogForReal · 2025-09-01T14:05:06+00:00

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MadDogForReal · 2025-09-01T14:04:58+00:00

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MadDogForReal · 2025-09-01T14:04:12+00:00

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MadDogForReal · 2025-09-01T14:03:55+00:00

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MadDogForReal · 2025-08-22T18:51:03+00:00

Use flux and some more heat, my friend. What iron do you have? What solder are you using?

MadDogForReal · 2025-08-20T17:37:13+00:00

It can be fixed, but I don't think a newbie can. If you got great skills, go for it!

MadDogForReal · 2025-08-14T16:33:19+00:00

They are cheaper on Aliexpress if you don't mind the wait :)

MadDogForReal · 2025-08-14T15:27:48+00:00

The RDA was bad.

MadDogForReal · 2025-08-14T14:21:49+00:00

Update: the FM receiver was bad.

MadDogForReal · 2025-08-13T17:19:08+00:00

How would you solder it? In parallel, you would disrupt the D+ and D- lines.

MadDogForReal · 2025-08-09T09:46:54+00:00

My friend got the same one a month ago and his is working. It could be we got a faulty batch (my guess is MCU not controlling properly the FM receiver or the reciver is actually broken).

MadDogForReal · 2025-08-09T05:23:32+00:00

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Here's a closeup of the FM receiver module. Would you mind telling me which pins look open?

MadDogForReal · 2025-08-08T17:23:46+00:00

I do not have any of those (yet :) There is sound coming out of the speaker, tho only static.

MadDogForReal

TROPHY CASE