AMTOOLS UK

  POUNDSHOP RADIO PROJECTS

     amps     POUNDSHOP RADIO  

COMPONENTS LIST

C1100n         (104)IC1       TDA 7088T

C2        0. 47        (473) R122K

C32000PF    (202)  R2150k

C4180PF      (181)  R35K6

C53300PF    (332)  TR1      2sc9014

C63300PF    (332)

C7  330pf     (331)

C882PF        (82)

C9220          (221)

C100.47Uf    ( 473)

C11       470pf      ( 471)

C12       0 .47       (473)

C13      100n        (104)

C14     2000PF     ( 202)

C15     220PF       (221)

C16      0.47         (473)

AMPS RADIO

As stated in the SPRAT article, the radios used in these projects are basically the same, and are based on the Philips TDA 7088T chip. 

There are very minor variations in component identity and layout.

The radio I  have available is virtually identical to the one shown in SPRAT.  Component layout is the same but numbering of components is different and there are a couple of very minor track changes on the pcb. 

To make life easy,  I have called my version the

AMPS radio (Amtools Pound Shop Radio), and am in the course of compiling detailed notes and circuits with illustrations, so that the differences can be seen at a glance.

These pages will be updated regularly to include new links and new design ideas.

If you have any ideas or interesting links which you would like to share with fellow constructors, please e mail me with details.

Any information used will be rightly attributed to its author.

More to follow, soon!

Mass produced in the Far East, these little radios can easily be modified to make direct conversion receivers.  There are endless other possibilities thanks to the heart of the radio, the TDA 7088T I.C. and to the inginuity of radio amateurs worldwide! 

AMPS RADIO MODS.25th March, 2006

The following instructions are as in SPRAT issue 125, page 4, with amendments for the Amtools radio which is virtually identical.

*Component numbers in brackets are those shown for the SPRAT version.

VCO

1.Lift R3 (R1) from pin 16

2.Remove all three switches.

3.Remove lamp

4.Connect pin 16 to pin 14 (Gnd)

5, 6.    Replace L1 (Osc. Coil, with parallel tuned circuit for 7Mhz or band required.

7.Cut track between R1(R2) and top of  volume control. (cw)

8.-

9.Connect loose end of R3 (R1) to volume control centre wiper.

10.      Connect top of volume control (cw) to Vp track.

11.      Replace C3 (C13) with 15pF to reduce tuning range.

R.F.

1.        Remove C8, 82pF.  (C1)

2.Connect pin 11 to antenna via 33pF capacitor.

3.Connect other antenna connection to pin 12.

A.F.

1.Replace C10, 40nF, with 100n capacitor.

2.Replace C4, 180pF (C10) with 5600pF

3.Replace C5, 3300pF, with 100n capacitor.

4.Remove C16, 47n.  Connect pin 15 to tr1 base with a 100n capacitor.

5.Remove C15.  Replace R2, 150K with 22K resistor.

6.Replace C6, 3300pF with 100nF capacitor.

7.Connect a 220uF capacitor from pin 3 to ground.