478
Item nr.
Grundig 98Asa Table top
Use ECC85 for MW conversion.
Data for Grundig 98Asa
| Production | Germany, 1964.
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| Bands | MW, FM (88-108MHz). |
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| Tubes | ECC85 (Conv.), EAF801 (IF), ECL86 (LF). |
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Semi-
conductors | B250C100 (rect), 2x AA119 (FM detector). |
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| Cabinet | Wood.
Size 49x19x15cm.
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| Power | AC 110/220V, 32W. |
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| Documents | Schema (at NVHR). |
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The Design
This is a complete AM/FM radio with just three tubes. The FM converter uses the ECC85 tube, as usual, but this converter is also used for MW. 
Because a single IF stage is a little bit poor for FM, the RF amplifier for FM is reflexed as a 10.7MHz IF stage. Picture shows the combined AM/FM tuner with ECC85 tube. The Grundig 98 was available in several variations. There were moulded and wood cabinets, and different FM ranges. Hence the wide variation in letters following the 98 in the type numbers.
| Obtained | 4/2018
from Piet; sn=137019266. |
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| Condition | 9; fully functional, just minor signs of usage. |
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| Disposed | Sold 5/2021. |
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This Object
I did a minor rehaul on October 15, 2018. The tuning needed a little lubrication. I replaced the coupling cap C26, the cathode capacitor C27, the Boucherot C31, and the ratio detector capacitor C22. Then the radio played very well, only some additional cleaning of the FM switch was needed. And there was some AF oscillation in the first minutes after switch on. I found out that the shield around the ECL86 was not grounded properly, and a little wire from this shield to ground solved this last problem.
Part of Gerard's Radio Corner.
Generated by SiteBuilder on
26/2/2024
by Gerard
(g.tel@uu.nl)